From e70d95531e86307255ef0c2fd88d08b6d120f778 Mon Sep 17 00:00:00 2001
From: Anthony Volk <14987227+anth-volk@users.noreply.github.com>
Date: Fri, 9 Oct 2026 04:52:21 +0400
Subject: [PATCH 1/7] Add Housing Benefit special standard earnings disregard

---
 changelog.d/hb-special-disregard.added.md     |   1 +
 .../means_test/income_disregard/special.yaml  |  16 +++
 .../housing_benefit_special_disregard.yaml    | 104 ++++++++++++++++++
 ...ing_benefit_applicable_income_disregard.py |  14 +--
 ...sing_benefit_special_earnings_disregard.py |  37 +++++++
 ...fit_special_earnings_disregard_eligible.py |  61 ++++++++++
 6 files changed, 224 insertions(+), 9 deletions(-)
 create mode 100644 changelog.d/hb-special-disregard.added.md
 create mode 100644 policyengine_uk/parameters/gov/dwp/housing_benefit/means_test/income_disregard/special.yaml
 create mode 100644 policyengine_uk/tests/policy/baseline/finance/benefit/family/housing_benefit/applicable_income/housing_benefit_special_disregard.yaml
 create mode 100644 policyengine_uk/variables/gov/dwp/housing_benefit/applicable_income/housing_benefit_special_earnings_disregard.py
 create mode 100644 policyengine_uk/variables/gov/dwp/housing_benefit/applicable_income/housing_benefit_special_earnings_disregard_eligible.py

diff --git a/changelog.d/hb-special-disregard.added.md b/changelog.d/hb-special-disregard.added.md
new file mode 100644
index 0000000000..8a9d2c8319
--- /dev/null
+++ b/changelog.d/hb-special-disregard.added.md
@@ -0,0 +1 @@
+Added the Housing Benefit special standard earnings disregard with regime-specific qualifying routes, explicit residual pre-assessment and no stacking with ordinary amounts.
diff --git a/policyengine_uk/parameters/gov/dwp/housing_benefit/means_test/income_disregard/special.yaml b/policyengine_uk/parameters/gov/dwp/housing_benefit/means_test/income_disregard/special.yaml
new file mode 100644
index 0000000000..e1f45b0c7d
--- /dev/null
+++ b/policyengine_uk/parameters/gov/dwp/housing_benefit/means_test/income_disregard/special.yaml
@@ -0,0 +1,16 @@
+description: Weekly Housing Benefit special standard earnings disregard, replacing the ordinary single or couple amount.
+values:
+  2015-04-01: 20
+metadata:
+  period: week
+  unit: currency-GBP
+  label: Housing Benefit special earnings disregard
+  reference:
+    - title: GB working-age earnings disregards, paragraphs 3 and 5 to 9
+      href: https://www.legislation.gov.uk/uksi/2006/213/schedule/4
+    - title: GB pension-age earnings disregards, paragraphs 1 to 7
+      href: https://www.legislation.gov.uk/uksi/2006/214/schedule/4
+    - title: NI working-age earnings disregards
+      href: https://www.legislation.gov.uk/nisr/2006/405/schedule/5
+    - title: NI pension-age earnings disregards
+      href: https://www.legislation.gov.uk/nisr/2006/406/schedule/5
diff --git a/policyengine_uk/tests/policy/baseline/finance/benefit/family/housing_benefit/applicable_income/housing_benefit_special_disregard.yaml b/policyengine_uk/tests/policy/baseline/finance/benefit/family/housing_benefit/applicable_income/housing_benefit_special_disregard.yaml
new file mode 100644
index 0000000000..af71a63ef8
--- /dev/null
+++ b/policyengine_uk/tests/policy/baseline/finance/benefit/family/housing_benefit/applicable_income/housing_benefit_special_disregard.yaml
@@ -0,0 +1,104 @@
+# Cases: working disability/severe; working carer-only; pension carer;
+# pension generic disability premium; pension/working DLA; non-dependant DLA;
+# pension/working blindness.
+- name: ENGLAND statutory regime distinguishes automatic qualifying routes
+  period: 2024
+  input:
+    country: [ENGLAND, ENGLAND, ENGLAND, ENGLAND, ENGLAND, ENGLAND, ENGLAND, ENGLAND, ENGLAND, ENGLAND]
+    housing_benefit_pension_age_regulations_apply: [false, false, false, true, true, true, false, true, true, false]
+    disability_premium: [100, 0, 0, 0, 100, 0, 0, 0, 0, 0]
+    severe_disability_premium: [0, 100, 0, 0, 0, 0, 0, 0, 0, 0]
+    carer_premium: [0, 0, 100, 100, 0, 0, 0, 0, 0, 0]
+    dla_sc: [0, 0, 0, 0, 0, 100, 100, 100, 0, 0]
+    dla_m: [0, 0, 0, 0, 0, 0, 0, 0, 0, 0]
+    pip_dl: [0, 0, 0, 0, 0, 0, 0, 0, 0, 0]
+    pip_m: [0, 0, 0, 0, 0, 0, 0, 0, 0, 0]
+    attendance_allowance: [0, 0, 0, 0, 0, 0, 0, 0, 0, 0]
+    armed_forces_independence_payment: [0, 0, 0, 0, 0, 0, 0, 0, 0, 0]
+    is_blind: [false, false, false, false, false, false, false, false, true, true]
+    is_claimant_or_partner: [true, true, true, true, true, true, true, false, true, true]
+    housing_benefit_net_earnings: [5000, 5000, 5000, 5000, 5000, 5000, 5000, 5000, 5000, 5000]
+    is_lone_parent: [false, false, false, false, false, false, false, false, false, false]
+    is_couple: [false, false, false, false, false, false, false, false, false, false]
+  output:
+    housing_benefit_special_earnings_disregard_eligible: [true, true, false, true, false, true, false, false, true, false]
+    housing_benefit_special_earnings_disregard: [1040, 1040, 260, 1040, 260, 1040, 260, 260, 1040, 260]
+
+# Cases: working disability/severe; working carer-only; pension carer;
+# pension generic disability premium; pension/working DLA; non-dependant DLA;
+# pension/working blindness.
+- name: NORTHERN_IRELAND statutory regime distinguishes automatic qualifying routes
+  period: 2024
+  input:
+    country: [NORTHERN_IRELAND, NORTHERN_IRELAND, NORTHERN_IRELAND, NORTHERN_IRELAND, NORTHERN_IRELAND, NORTHERN_IRELAND, NORTHERN_IRELAND, NORTHERN_IRELAND, NORTHERN_IRELAND, NORTHERN_IRELAND]
+    housing_benefit_pension_age_regulations_apply: [false, false, false, true, true, true, false, true, true, false]
+    disability_premium: [100, 0, 0, 0, 100, 0, 0, 0, 0, 0]
+    severe_disability_premium: [0, 100, 0, 0, 0, 0, 0, 0, 0, 0]
+    carer_premium: [0, 0, 100, 100, 0, 0, 0, 0, 0, 0]
+    dla_sc: [0, 0, 0, 0, 0, 100, 100, 100, 0, 0]
+    dla_m: [0, 0, 0, 0, 0, 0, 0, 0, 0, 0]
+    pip_dl: [0, 0, 0, 0, 0, 0, 0, 0, 0, 0]
+    pip_m: [0, 0, 0, 0, 0, 0, 0, 0, 0, 0]
+    attendance_allowance: [0, 0, 0, 0, 0, 0, 0, 0, 0, 0]
+    armed_forces_independence_payment: [0, 0, 0, 0, 0, 0, 0, 0, 0, 0]
+    is_blind: [false, false, false, false, false, false, false, false, true, true]
+    is_claimant_or_partner: [true, true, true, true, true, true, true, false, true, true]
+    housing_benefit_net_earnings: [5000, 5000, 5000, 5000, 5000, 5000, 5000, 5000, 5000, 5000]
+    is_lone_parent: [false, false, false, false, false, false, false, false, false, false]
+    is_couple: [false, false, false, false, false, false, false, false, false, false]
+  output:
+    housing_benefit_special_earnings_disregard_eligible: [true, true, false, true, false, true, false, false, true, false]
+    housing_benefit_special_earnings_disregard: [1040, 1040, 260, 1040, 260, 1040, 260, 260, 1040, 260]
+
+- name: Standard replacement, lone-parent precedence and earnings cap
+  period: 2024
+  input:
+    housing_benefit_special_earnings_disregard_eligible: [true, true, true, true, false, false]
+    housing_benefit_net_earnings: [5000, 5000, 5000, 500, 5000, 5000]
+    is_couple: [false, true, false, true, false, true]
+    is_lone_parent: [false, false, true, false, false, false]
+    housing_benefit_specified_or_temporary_accommodation_disregard: [0, 0, 0, 0, 0, 0]
+    housing_benefit_applicable_income_childcare_element: [0, 0, 0, 0, 0, 0]
+    meets_housing_benefit_additional_earnings_disregard_conditions: [false, false, false, false, false, false]
+    housing_benefit_on_passporting_benefit: [false, false, false, false, false, false]
+  output:
+    housing_benefit_applicable_income_disregard: [1040, 1040, 1300, 500, 260, 520]
+
+- name: Special standard amount participates in additional-disregard threshold
+  period: 2024
+  absolute_error_margin: 0.01
+  input:
+    housing_benefit_special_earnings_disregard_eligible: [true, true, true]
+    housing_benefit_net_earnings: [1929.19, 1929.20, 5000]
+    is_couple: [false, true, false]
+    is_lone_parent: [false, false, false]
+    housing_benefit_specified_or_temporary_accommodation_disregard: [0, 0, 0]
+    housing_benefit_applicable_income_childcare_element: [0, 0, 0]
+    meets_housing_benefit_additional_earnings_disregard_conditions: [true, true, true]
+    housing_benefit_on_passporting_benefit: [false, false, true]
+  output:
+    housing_benefit_applicable_income_disregard: [1040, 1929.20, 5000]
+
+- name: A zero special-amount reform is not replaced with the ordinary amount
+  period: 2024
+  input:
+    gov.dwp.housing_benefit.means_test.income_disregard.special: 0
+    housing_benefit_special_earnings_disregard_eligible: true
+    housing_benefit_net_earnings: 5000
+    is_lone_parent: false
+    is_couple: true
+  output:
+    housing_benefit_special_earnings_disregard: 0
+
+- name: Missing residual qualification preserves ordinary treatment
+  period: 2024
+  input:
+    disability_premium: 0
+    severe_disability_premium: 0
+    housing_benefit_pension_age_regulations_apply: false
+    housing_benefit_net_earnings: 5000
+    is_lone_parent: false
+    is_couple: false
+  output:
+    housing_benefit_special_earnings_disregard_eligible: false
+    housing_benefit_special_earnings_disregard: 260
diff --git a/policyengine_uk/variables/gov/dwp/housing_benefit/applicable_income/housing_benefit_applicable_income_disregard.py b/policyengine_uk/variables/gov/dwp/housing_benefit/applicable_income/housing_benefit_applicable_income_disregard.py
index a7600bf518..7de5c94a3d 100644
--- a/policyengine_uk/variables/gov/dwp/housing_benefit/applicable_income/housing_benefit_applicable_income_disregard.py
+++ b/policyengine_uk/variables/gov/dwp/housing_benefit/applicable_income/housing_benefit_applicable_income_disregard.py
@@ -20,10 +20,11 @@ class housing_benefit_applicable_income_disregard(Variable):
         "(housing_benefit_on_passporting_benefit) has all earnings "
         "disregarded, at any age: the working-age Regulations then apply "
         "(SI 2006/213 reg 5(1)(b)). The "
-        "£20 disregards for disabled people, carers and some part-time "
-        "occupations are not modelled, nor is the working-age permitted work "
+        "£20 standard disregard uses established qualifying routes or an "
+        "explicit full-amount pre-assessment, without reconstructing partial "
+        "carer/occupation earnings allocations. The permitted-work "
         "disregard (Sch 4 para 10A), which replaces paras 3 to 10 but not "
-        "para 18."
+        "para 18, is not yet modelled here."
     )
     definition_period = YEAR
     unit = GBP
@@ -42,12 +43,7 @@ def formula(benunit, period, parameters):
         p = parameters(period).gov.dwp.housing_benefit.means_test.income_disregard
         net_earnings = benunit("housing_benefit_net_earnings", period)
         # Working age Sch 4 paras 4, 7 and 10; pension age Sch 4 paras 2 and 7.
-        weekly_amount = select(
-            [benunit("is_lone_parent", period), benunit("is_couple", period)],
-            [p.lone_parent, p.couple],
-            default=p.single,
-        )
-        standard = min_(weekly_amount * WEEKS_IN_YEAR, net_earnings)
+        standard = benunit("housing_benefit_special_earnings_disregard", period)
         # Working age Sch 4 para 18 (NI Sch 5 para 18), from 5 October 2026:
         # specified or temporary accommodation. It applies alongside paras 3
         # to 10A, none of which excludes it, and takes the earnings they
diff --git a/policyengine_uk/variables/gov/dwp/housing_benefit/applicable_income/housing_benefit_special_earnings_disregard.py b/policyengine_uk/variables/gov/dwp/housing_benefit/applicable_income/housing_benefit_special_earnings_disregard.py
new file mode 100644
index 0000000000..04d731487a
--- /dev/null
+++ b/policyengine_uk/variables/gov/dwp/housing_benefit/applicable_income/housing_benefit_special_earnings_disregard.py
@@ -0,0 +1,37 @@
+from policyengine_uk.model_api import *
+
+
+class housing_benefit_special_earnings_disregard(Variable):
+    value_type = float
+    entity = BenUnit
+    definition_period = YEAR
+    unit = GBP
+    label = "Housing Benefit selected standard earnings disregard"
+    documentation = (
+        "Standard disregard selected before the additional/accommodation "
+        "amounts: lone-parent precedence, otherwise the special amount for "
+        "a qualifying family, otherwise the ordinary couple/single amount. "
+        "It is a replacement, not £20 added to £5 or £10. The total standard "
+        "deduction is capped at the claimant's and partner's net earnings."
+    )
+    reference = (
+        "https://www.legislation.gov.uk/uksi/2006/213/schedule/4",
+        "https://www.legislation.gov.uk/uksi/2006/214/schedule/4",
+        "https://www.legislation.gov.uk/nisr/2006/405/schedule/5",
+        "https://www.legislation.gov.uk/nisr/2006/406/schedule/5",
+    )
+
+    def formula(benunit, period, parameters):
+        p = parameters(period).gov.dwp.housing_benefit.means_test.income_disregard
+        weekly = select(
+            [
+                benunit("is_lone_parent", period),
+                benunit("housing_benefit_special_earnings_disregard_eligible", period),
+                benunit("is_couple", period),
+            ],
+            [p.lone_parent, p.special, p.couple],
+            default=p.single,
+        )
+        return min_(
+            weekly * WEEKS_IN_YEAR, benunit("housing_benefit_net_earnings", period)
+        )
diff --git a/policyengine_uk/variables/gov/dwp/housing_benefit/applicable_income/housing_benefit_special_earnings_disregard_eligible.py b/policyengine_uk/variables/gov/dwp/housing_benefit/applicable_income/housing_benefit_special_earnings_disregard_eligible.py
new file mode 100644
index 0000000000..5c15427da6
--- /dev/null
+++ b/policyengine_uk/variables/gov/dwp/housing_benefit/applicable_income/housing_benefit_special_earnings_disregard_eligible.py
@@ -0,0 +1,61 @@
+from policyengine_uk.model_api import *
+
+
+class housing_benefit_special_earnings_disregard_eligible(Variable):
+    value_type = bool
+    entity = BenUnit
+    definition_period = YEAR
+    default_value = False
+    label = "Qualifies for the full Housing Benefit special earnings disregard"
+    documentation = (
+        "Whether the full special standard amount may legally be deducted "
+        "from the benefit unit's combined earnings, subject to the earnings "
+        "cap. Derived for working-age disability/severe-premium routes and "
+        "pension-age qualifying benefit receipt, blindness or carer premium. "
+        "Other full-amount routes may be pre-assessed as an input, including "
+        "the applicable job/partner earnings allocation: mere occupation or "
+        "carer status is not sufficient. Partial carer/occupation allocations "
+        "below the full amount are not reconstructed by this Boolean. Existing "
+        "premium/benefit qualification approximations are inherited. No "
+        "dataset mapping for residual pre-assessment is verified; a false "
+        "fallback may omit qualifying ESA phase/history/occupation routes."
+    )
+    reference = (
+        "https://www.legislation.gov.uk/uksi/2006/213/schedule/4",
+        "https://www.legislation.gov.uk/uksi/2006/214/schedule/4",
+        "https://www.legislation.gov.uk/nisr/2006/405/schedule/5",
+        "https://www.legislation.gov.uk/nisr/2006/406/schedule/5",
+    )
+
+    def formula(benunit, period, parameters):
+        working = (benunit("disability_premium", period) > 0) | (
+            benunit("severe_disability_premium", period) > 0
+        )
+        person = benunit.members
+        qualifying_receipt = (
+            add(
+                person,
+                period,
+                [
+                    "attendance_allowance",
+                    "dla_sc",
+                    "dla_m",
+                    "pip_dl",
+                    "pip_m",
+                    "armed_forces_independence_payment",
+                ],
+            )
+            > 0
+        )
+        pension = benunit.any(
+            person("is_claimant_or_partner", period)
+            & (qualifying_receipt | person("is_blind", period))
+        ) | (benunit("carer_premium", period) > 0)
+        # Working-age carer/occupation routes restrict which person's/job's
+        # earnings may be disregarded. Do not automatically apply £20 to an
+        # ordinary earner solely because their non-earning partner cares.
+        return where(
+            benunit("housing_benefit_pension_age_regulations_apply", period),
+            pension,
+            working,
+        )

From 6e68f23fafef3a1e0a1718bd5d1e4bc0fa860c72 Mon Sep 17 00:00:00 2001
From: Anthony Volk <14987227+anth-volk@users.noreply.github.com>
Date: Fri, 9 Oct 2026 18:49:18 +0400
Subject: [PATCH 2/7] Update disabled-worker regression for HB special earnings
 disregard

---
 ...ng_benefit_applicable_income_disregard.yaml | 18 ++++++++----------
 1 file changed, 8 insertions(+), 10 deletions(-)

diff --git a/policyengine_uk/tests/policy/baseline/finance/benefit/family/housing_benefit/applicable_income/housing_benefit_applicable_income_disregard.yaml b/policyengine_uk/tests/policy/baseline/finance/benefit/family/housing_benefit/applicable_income/housing_benefit_applicable_income_disregard.yaml
index 7cf5e90192..a2dcadd7cd 100644
--- a/policyengine_uk/tests/policy/baseline/finance/benefit/family/housing_benefit/applicable_income/housing_benefit_applicable_income_disregard.yaml
+++ b/policyengine_uk/tests/policy/baseline/finance/benefit/family/housing_benefit/applicable_income/housing_benefit_applicable_income_disregard.yaml
@@ -430,7 +430,7 @@
     # One member must work 30 hours; hours are not added across the couple.
     housing_benefit_applicable_income_disregard: 520 # £10 × 52
 
-- name: Disabled single person working 20 hours gets £5 plus the additional disregard (model limitation; the law gives £20 plus it)
+- name: Disabled single person working 20 hours gets £20 plus the additional disregard
   period: 2026
   absolute_error_margin: 0.01
   input:
@@ -448,15 +448,13 @@
     # Para 17(2)(b)(iv)(aa): a single claimant with the disability premium
     # working 16 hours or more meets the condition.
     meets_housing_benefit_additional_earnings_disregard_conditions: true
-    # KNOWN LIMITATION: the law gives £1,929.20. Intended model limitation.
-    # In law the same disability premium brings in
-    # the £20 disregard in place of £5: Sch 4 para 3(2), "This paragraph
-    # applies where the claimant's applicable amount includes an amount by
-    # way of the disability premium". The law gives (£20 + £17.10) × 52 =
-    # £1,929.20 (£8,000 ≥ £1,040 + £889.20). The £20 disregards are out of
-    # scope for this change and tracked as a follow-up; until then the model
-    # gives (£5 + £17.10) × 52.
-    housing_benefit_applicable_income_disregard: 1_149.20
+    # The disability premium gives the £20 standard disregard under Sch 4
+    # para 3(2), replacing £5. Net earnings cover that amount and the
+    # additional disregard: £8,000 ≥ £1,040 + £889.20.
+    # (£20 + £17.10) × 52 = £1,929.20.
+    # https://www.legislation.gov.uk/uksi/2006/213/schedule/4/paragraph/3
+    # https://www.legislation.gov.uk/uksi/2006/213/schedule/4/paragraph/17
+    housing_benefit_applicable_income_disregard: 1_929.20
 
 - name: Working-age claimant on Income Support has all earnings disregarded
   period: 2026

From de8eb6a78b446569b41d856e0d03e1ab20afbef8 Mon Sep 17 00:00:00 2001
From: Max Ghenis <mghenis@gmail.com>
Date: Sat, 24 Oct 2026 18:15:14 -0400
Subject: [PATCH 3/7] =?UTF-8?q?Account=20for=20the=20special=20=C2=A320=20?=
 =?UTF-8?q?disregard=20in=20three=20HB=20property=20tests?=
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Three property tests that predate this PR assumed the £5/£10/£25
standard disregards only. The PR is a draft, so CI had not run them:

- test_pension_age_and_working_age_schedules_agree compared the two
  schedules for every family. The special £20 routes differ by design
  (working age: a disability or severe disability premium; pension age:
  receipt of a listed benefit, blindness or a carer premium), so the test
  now compares the disregards only where the model's eligibility flag
  agrees, and asserts that the flag agrees for every family with no
  disabled adult.
- test_differential_against_the_old_flat_formula now expects
  min(£20 x 52, net earnings) for a qualifying single person or couple; a
  lone parent keeps £25.
- The para 18 differential's statutory reference now takes the para 3
  special £20 from the model's eligibility flag, as it already takes the
  para 17(2) work condition. test_housing_benefit_earnings_disregard_properties.py
  tests the flag itself.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
---
 ...g_benefit_earnings_disregard_properties.py | 33 +++++++++++++++----
 ...fied_accommodation_disregard_properties.py | 31 ++++++++++++-----
 2 files changed, 49 insertions(+), 15 deletions(-)

diff --git a/policyengine_uk/tests/test_housing_benefit_earnings_disregard_properties.py b/policyengine_uk/tests/test_housing_benefit_earnings_disregard_properties.py
index 06c0663331..9aee1a7a90 100644
--- a/policyengine_uk/tests/test_housing_benefit_earnings_disregard_properties.py
+++ b/policyengine_uk/tests/test_housing_benefit_earnings_disregard_properties.py
@@ -2,7 +2,8 @@
 
 SI 2006/213 Sch 4 (working age) and SI 2006/214 Sch 4 (pension age) disregard
 £25 a week of a lone parent's net earnings, £10 of a couple's and £5 of anyone
-else's, plus the £17.10 additional earnings disregard where a work condition
+else's, or £20 in place of the £5 or £10 for a family that qualifies for the
+special disregard (housing_benefit_special_earnings_disregard_eligible), plus the £17.10 additional earnings disregard where a work condition
 is met and net earnings at least equal the other disregards, the deductible
 childcare charges and £17.10. A claimant who, or whose partner, is on
 Universal Credit, Income Support, income-based JSA or income-related ESA has
@@ -28,11 +29,19 @@
    over, where nothing age-dependent (para 12, the age-25 test, National
    Insurance above State Pension age) can differ between the two groups, so
    it pins the current behaviour rather than independently testing the two
-   schedules.
+   schedules. Intended difference: the £20 special disregard has different
+   conditions at each age. At working age it follows the disability premium,
+   which the model grants on the disability flag the draws set; at pension age
+   it needs receipt of a listed benefit, blindness or the carer premium (SI
+   2006/214 Sch 4 paras 4 and 5), none of which the draws supply. The
+   comparison therefore covers families whose special eligibility is the same
+   at both ages, which includes every family without a disabled adult.
 7. Differential against the old flat formula (£5/£10/£25 by family type, plus
    £37.10 for summed hours over 30, or 16 for lone parents), read without
    CPI uprating. They agree for families whose net earnings cover the flat
-   amount and to whom neither formula gives the additional disregard. They
+   amount and to whom neither formula gives the additional disregard or the
+   special disregard; a couple or single person who qualifies for the special
+   disregard, and whose net earnings cover £20, gets £20 instead. They
    must differ where net earnings fall below the flat amount (the new
    disregard is the net earnings) and for families without earnings (the new
    disregard is zero).
@@ -159,6 +168,7 @@ def situation(units, earnings_bump=0.0, income_support=0.0, age_map=None):
     "housing_benefit_applicable_income",
     "housing_benefit_applicable_income_childcare_element",
     "meets_housing_benefit_additional_earnings_disregard_conditions",
+    "housing_benefit_special_earnings_disregard_eligible",
 ]
 
 
@@ -246,8 +256,13 @@ def test_pension_age_and_working_age_schedules_agree(units):
     # Map 25-60 onto 67-90, keeping everyone at or over 25.
     pension_age = calculate(units, age_map=lambda age: 67 + (age - 25) * 23 // 35)
     key = "housing_benefit_applicable_income_disregard"
+    special = "housing_benefit_special_earnings_disregard_eligible"
     for i, unit in enumerate(units):
-        assert abs(working_age[key][i] - pension_age[key][i]) < 0.01, unit
+        if not any(adult["disabled"] for adult in unit["adults"]):
+            # Nothing else in the draws can make the two routes differ.
+            assert working_age[special][i] == pension_age[special][i], unit
+        if working_age[special][i] == pension_age[special][i]:
+            assert abs(working_age[key][i] - pension_age[key][i]) < 0.01, unit
 
 
 @PROPERTY_SETTINGS
@@ -259,6 +274,7 @@ def test_differential_against_the_old_flat_formula(units):
     additional = values[
         "meets_housing_benefit_additional_earnings_disregard_conditions"
     ].astype(bool)
+    special = values["housing_benefit_special_earnings_disregard_eligible"].astype(bool)
     for i, unit in enumerate(units):
         old = old_flat_formula(unit)
         flat = OLD_FLAT[unit["shape"]] * WEEKS
@@ -272,8 +288,13 @@ def test_differential_against_the_old_flat_formula(units):
             assert abs(disregard[i] - net[i]) < 0.01, unit
             assert disregard[i] < old, unit
         elif not old_worker and not additional[i]:
-            # Agree: the flat amount, without CPI uprating.
-            assert abs(disregard[i] - old) < 0.01, unit
+            if special[i] and unit["shape"] != "lone_parent":
+                # Must differ: £20 replaces the flat £5 or £10 (lone parents
+                # keep £25, which takes precedence).
+                assert abs(disregard[i] - min(20 * WEEKS, net[i])) < 0.01, unit
+            else:
+                # Agree: the flat amount, without CPI uprating.
+                assert abs(disregard[i] - old) < 0.01, unit
 
 
 @PROPERTY_SETTINGS
diff --git a/policyengine_uk/tests/test_housing_benefit_specified_accommodation_disregard_properties.py b/policyengine_uk/tests/test_housing_benefit_specified_accommodation_disregard_properties.py
index 0306c17183..85efbaf541 100644
--- a/policyengine_uk/tests/test_housing_benefit_specified_accommodation_disregard_properties.py
+++ b/policyengine_uk/tests/test_housing_benefit_specified_accommodation_disregard_properties.py
@@ -9,8 +9,8 @@
 claimant or lone parent under 25, £77.73 at 25 or over; for a couple £97.33
 where both are under 18, £61.53 where one is 18 or over but both are under
 25, and £119.70 where one is 25 or over. A couple has one amount. It is added
-to the £5/£10/£25 disregards (paras 10, 7 and 4), and para 17(3)(a) counts it
-in the £17.10 additional disregard's earnings test. The pension-age
+to the £5/£10/£20/£25 disregards (paras 10, 7, 3 and 4), and para 17(3)(a)
+counts it in the £17.10 additional disregard's earnings test. The pension-age
 Regulations (SI 2006/214; NI SR 2006/406) have no such disregard.
 
 Invariants, for 2027 (the first fiscal year the model reads with para 18 in
@@ -32,9 +32,12 @@
 5. Differential: the model agrees with a reference written from the
    statutory text. The reference is independent for the para 18 bands and
    gates (amounts hard-coded from the instrument, ages, family type, earner
-   and pension-age status from the generated inputs) and for how paras 4, 7,
-   10, 17 and 18 combine. It takes net earnings, deductible childcare and
-   the para 17(2) work condition from the model, which other tests cover.
+   and pension-age status from the generated inputs) and for how paras 3, 4,
+   7, 10, 17 and 18 combine. It takes net earnings, deductible childcare,
+   the para 17(2) work condition and whether the para 3 special £20 applies
+   from the model, which other tests cover
+   (test_housing_benefit_earnings_disregard_properties.py tests the special
+   £20).
    Explicit examples pin the age boundaries (couples aged 17/17, 17/18 and
    24/25; single claimants and lone parents aged 24 and 25).
 6. Scope: families whose claimant and partner are all over State Pension
@@ -80,6 +83,8 @@
 }
 # Paras 4, 7 and 10, and para 17.
 BASE_WEEKLY = {"single": 5, "lone_parent": 25, "couple": 10, "couple_with_children": 10}
+# Para 3: replaces the single or couple amount; a lone parent keeps £25.
+SPECIAL_WEEKLY = 20
 ADDITIONAL_WEEKLY = 17.10
 MAX_ANNUAL = (25 + COUPLE_25_PLUS + ADDITIONAL_WEEKLY) * WEEKS
 
@@ -198,6 +203,7 @@ def situation(units, earnings_bump=0.0, income_support=0.0, accommodation=None):
     "housing_benefit_applicable_income",
     "housing_benefit_applicable_income_childcare_element",
     "meets_housing_benefit_additional_earnings_disregard_conditions",
+    "housing_benefit_special_earnings_disregard_eligible",
     "housing_benefit_pension_age_regulations_apply",
 ]
 
@@ -229,10 +235,14 @@ def reference_para_18_weekly(unit):
     return SINGLE_25_PLUS if eldest >= 25 else SINGLE_UNDER_25
 
 
-def reference_disregard(unit, net, childcare, work_condition):
-    """Paras 4, 7, 10, 17 and 18 combined, from net earnings, the deductible
-    childcare charges and whether a para 17(2) work condition is met."""
-    standard = min(BASE_WEEKLY[unit["shape"]] * WEEKS, net)
+def reference_disregard(unit, net, childcare, work_condition, special=False):
+    """Paras 3, 4, 7, 10, 17 and 18 combined, from net earnings, the deductible
+    childcare charges, whether a para 17(2) work condition is met and whether
+    the para 3 special £20 applies."""
+    weekly = BASE_WEEKLY[unit["shape"]]
+    if special and unit["shape"] != "lone_parent":
+        weekly = SPECIAL_WEEKLY
+    standard = min(weekly * WEEKS, net)
     accommodation = min(reference_para_18_weekly(unit) * WEEKS, net - standard)
     additional = ADDITIONAL_WEEKLY * WEEKS
     covers = round(net, 2) >= round(
@@ -368,6 +378,9 @@ def test_differential_against_the_statutory_reference(units):
                     "meets_housing_benefit_additional_earnings_disregard_conditions"
                 ][i]
             ),
+            special=bool(
+                values["housing_benefit_special_earnings_disregard_eligible"][i]
+            ),
         )
         total = values["housing_benefit_applicable_income_disregard"][i]
         assert abs(total - expected) < 0.02, (unit, total, expected)

From 375d7727a97d6baddaa9fe8d71ab78b6e067e781 Mon Sep 17 00:00:00 2001
From: Max Ghenis <mghenis@gmail.com>
Date: Sun, 25 Oct 2026 01:24:45 -0400
Subject: [PATCH 4/7] Complete pension-age HB disability receipt routes

Include SDA and disability-related WTC, retain claimant/partner boundaries, and pin the selected standard directly alongside GB/NI receipt regressions.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
---
 .../housing_benefit_special_disregard.yaml    | 271 ++++++++++++++++++
 ...fit_special_earnings_disregard_eligible.py |  53 +++-
 2 files changed, 320 insertions(+), 4 deletions(-)

diff --git a/policyengine_uk/tests/policy/baseline/finance/benefit/family/housing_benefit/applicable_income/housing_benefit_special_disregard.yaml b/policyengine_uk/tests/policy/baseline/finance/benefit/family/housing_benefit/applicable_income/housing_benefit_special_disregard.yaml
index af71a63ef8..342e19feec 100644
--- a/policyengine_uk/tests/policy/baseline/finance/benefit/family/housing_benefit/applicable_income/housing_benefit_special_disregard.yaml
+++ b/policyengine_uk/tests/policy/baseline/finance/benefit/family/housing_benefit/applicable_income/housing_benefit_special_disregard.yaml
@@ -50,6 +50,276 @@
     housing_benefit_special_earnings_disregard_eligible: [true, true, false, true, false, true, false, false, true, false]
     housing_benefit_special_earnings_disregard: [1040, 1040, 260, 1040, 260, 1040, 260, 260, 1040, 260]
 
+# Cases: SDA; WTC disability; WTC severe disability; AA; DLA mobility;
+# PIP daily living; PIP mobility; AFIP; WTC element without an award;
+# WTC award without either disability element. Each claimant is pension-age,
+# is not a lone parent and has more than £20 a week in net earnings.
+- name: ENGLAND pension-age qualifying receipt matrix
+  period: 2024
+  input:
+    country: [ENGLAND, ENGLAND, ENGLAND, ENGLAND, ENGLAND, ENGLAND, ENGLAND, ENGLAND, ENGLAND, ENGLAND]
+    age: [70, 70, 70, 70, 70, 70, 70, 70, 70, 70]
+    housing_benefit_pension_age_regulations_apply: [true, true, true, true, true, true, true, true, true, true]
+    carer_premium: [0, 0, 0, 0, 0, 0, 0, 0, 0, 0]
+    sda: [100, 0, 0, 0, 0, 0, 0, 0, 0, 0]
+    working_tax_credit: [0, 100, 100, 0, 0, 0, 0, 0, 0, 100]
+    WTC_disabled_element: [0, 100, 0, 0, 0, 0, 0, 0, 100, 0]
+    WTC_severely_disabled_element: [0, 0, 100, 0, 0, 0, 0, 0, 0, 0]
+    attendance_allowance: [0, 0, 0, 100, 0, 0, 0, 0, 0, 0]
+    dla_sc: [0, 0, 0, 0, 0, 0, 0, 0, 0, 0]
+    dla_m: [0, 0, 0, 0, 100, 0, 0, 0, 0, 0]
+    pip_dl: [0, 0, 0, 0, 0, 100, 0, 0, 0, 0]
+    pip_m: [0, 0, 0, 0, 0, 0, 100, 0, 0, 0]
+    armed_forces_independence_payment: [0, 0, 0, 0, 0, 0, 0, 100, 0, 0]
+    is_blind: [false, false, false, false, false, false, false, false, false, false]
+    is_claimant_or_partner: [true, true, true, true, true, true, true, true, true, true]
+    housing_benefit_net_earnings: [5000, 5000, 5000, 5000, 5000, 5000, 5000, 5000, 5000, 5000]
+    is_lone_parent: [false, false, false, false, false, false, false, false, false, false]
+    is_couple: [false, false, false, false, false, false, false, false, false, false]
+  output:
+    housing_benefit_special_earnings_disregard_eligible: [true, true, true, true, true, true, true, true, false, false]
+    housing_benefit_special_earnings_disregard: [1040, 1040, 1040, 1040, 1040, 1040, 1040, 1040, 260, 260]
+
+- name: ENGLAND pension-age partner SDA qualifies the couple
+  period: 2024
+  input:
+    people:
+      claimant:
+        age: 72
+        is_claimant_or_partner: true
+        sda: 0
+      partner:
+        age: 70
+        is_claimant_or_partner: true
+        sda: 100
+    benunits:
+      couple:
+        members: [claimant, partner]
+        housing_benefit_pension_age_regulations_apply: true
+        housing_benefit_net_earnings: 5000
+        carer_premium: 0
+        working_tax_credit: 0
+    households:
+      household:
+        members: [claimant, partner]
+        country: ENGLAND
+  output:
+    is_lone_parent: false
+    is_couple: true
+    housing_benefit_special_earnings_disregard_eligible: true
+    housing_benefit_special_earnings_disregard: 1040
+
+- name: ENGLAND adult non-dependant SDA and disability WTC do not qualify the pension-age couple
+  period: 2024
+  input:
+    people:
+      claimant:
+        age: 72
+        is_claimant_or_partner: true
+        sda: 0
+      partner:
+        age: 70
+        is_claimant_or_partner: true
+        sda: 0
+      adult_non_dependant:
+        age: 40
+        # Claimant of their own benefit unit, never of the pensioner couple.
+        is_claimant_or_partner: true
+        sda: 100
+    benunits:
+      couple:
+        members: [claimant, partner]
+        housing_benefit_pension_age_regulations_apply: true
+        housing_benefit_net_earnings: 5000
+        carer_premium: 0
+        working_tax_credit: 0
+        WTC_disabled_element: 0
+        WTC_severely_disabled_element: 0
+      non_dependant:
+        members: [adult_non_dependant]
+        housing_benefit_pension_age_regulations_apply: false
+        housing_benefit_net_earnings: 0
+        disability_premium: 0
+        severe_disability_premium: 0
+        working_tax_credit: 100
+        WTC_disabled_element: 100
+        WTC_severely_disabled_element: 0
+    households:
+      household:
+        members: [claimant, partner, adult_non_dependant]
+        country: ENGLAND
+  output:
+    is_lone_parent: [false, false]
+    is_couple: [true, false]
+    housing_benefit_special_earnings_disregard_eligible: [false, false]
+    housing_benefit_special_earnings_disregard: [520, 0]
+
+- name: ENGLAND qualifying young person's disability receipt does not qualify the pension-age claimant
+  period: 2024
+  input:
+    people:
+      claimant:
+        age: 72
+        is_claimant_or_partner: true
+        pip_m: 0
+      qualifying_young_person:
+        age: 18
+        is_claimant_or_partner: false
+        is_in_non_advanced_education: true
+        pip_m: 100
+    benunits:
+      family:
+        members: [claimant, qualifying_young_person]
+        housing_benefit_pension_age_regulations_apply: true
+        housing_benefit_net_earnings: 5000
+        carer_premium: 0
+        working_tax_credit: 0
+        # Isolate receipt scoping from the independent lone-parent route.
+        is_lone_parent: false
+    households:
+      household:
+        members: [claimant, qualifying_young_person]
+        country: ENGLAND
+  output:
+    is_couple: false
+    housing_benefit_special_earnings_disregard_eligible: false
+    housing_benefit_special_earnings_disregard: 260
+
+# Cases: SDA; WTC disability; WTC severe disability; AA; DLA mobility;
+# PIP daily living; PIP mobility; AFIP; WTC element without an award;
+# WTC award without either disability element. Each claimant is pension-age,
+# is not a lone parent and has more than £20 a week in net earnings.
+- name: NORTHERN_IRELAND pension-age qualifying receipt matrix
+  period: 2024
+  input:
+    country: [NORTHERN_IRELAND, NORTHERN_IRELAND, NORTHERN_IRELAND, NORTHERN_IRELAND, NORTHERN_IRELAND, NORTHERN_IRELAND, NORTHERN_IRELAND, NORTHERN_IRELAND, NORTHERN_IRELAND, NORTHERN_IRELAND]
+    age: [70, 70, 70, 70, 70, 70, 70, 70, 70, 70]
+    housing_benefit_pension_age_regulations_apply: [true, true, true, true, true, true, true, true, true, true]
+    carer_premium: [0, 0, 0, 0, 0, 0, 0, 0, 0, 0]
+    sda: [100, 0, 0, 0, 0, 0, 0, 0, 0, 0]
+    working_tax_credit: [0, 100, 100, 0, 0, 0, 0, 0, 0, 100]
+    WTC_disabled_element: [0, 100, 0, 0, 0, 0, 0, 0, 100, 0]
+    WTC_severely_disabled_element: [0, 0, 100, 0, 0, 0, 0, 0, 0, 0]
+    attendance_allowance: [0, 0, 0, 100, 0, 0, 0, 0, 0, 0]
+    dla_sc: [0, 0, 0, 0, 0, 0, 0, 0, 0, 0]
+    dla_m: [0, 0, 0, 0, 100, 0, 0, 0, 0, 0]
+    pip_dl: [0, 0, 0, 0, 0, 100, 0, 0, 0, 0]
+    pip_m: [0, 0, 0, 0, 0, 0, 100, 0, 0, 0]
+    armed_forces_independence_payment: [0, 0, 0, 0, 0, 0, 0, 100, 0, 0]
+    is_blind: [false, false, false, false, false, false, false, false, false, false]
+    is_claimant_or_partner: [true, true, true, true, true, true, true, true, true, true]
+    housing_benefit_net_earnings: [5000, 5000, 5000, 5000, 5000, 5000, 5000, 5000, 5000, 5000]
+    is_lone_parent: [false, false, false, false, false, false, false, false, false, false]
+    is_couple: [false, false, false, false, false, false, false, false, false, false]
+  output:
+    housing_benefit_special_earnings_disregard_eligible: [true, true, true, true, true, true, true, true, false, false]
+    housing_benefit_special_earnings_disregard: [1040, 1040, 1040, 1040, 1040, 1040, 1040, 1040, 260, 260]
+
+- name: NORTHERN_IRELAND pension-age partner SDA qualifies the couple
+  period: 2024
+  input:
+    people:
+      claimant:
+        age: 72
+        is_claimant_or_partner: true
+        sda: 0
+      partner:
+        age: 70
+        is_claimant_or_partner: true
+        sda: 100
+    benunits:
+      couple:
+        members: [claimant, partner]
+        housing_benefit_pension_age_regulations_apply: true
+        housing_benefit_net_earnings: 5000
+        carer_premium: 0
+        working_tax_credit: 0
+    households:
+      household:
+        members: [claimant, partner]
+        country: NORTHERN_IRELAND
+  output:
+    is_lone_parent: false
+    is_couple: true
+    housing_benefit_special_earnings_disregard_eligible: true
+    housing_benefit_special_earnings_disregard: 1040
+
+- name: NORTHERN_IRELAND adult non-dependant SDA and disability WTC do not qualify the pension-age couple
+  period: 2024
+  input:
+    people:
+      claimant:
+        age: 72
+        is_claimant_or_partner: true
+        sda: 0
+      partner:
+        age: 70
+        is_claimant_or_partner: true
+        sda: 0
+      adult_non_dependant:
+        age: 40
+        # Claimant of their own benefit unit, never of the pensioner couple.
+        is_claimant_or_partner: true
+        sda: 100
+    benunits:
+      couple:
+        members: [claimant, partner]
+        housing_benefit_pension_age_regulations_apply: true
+        housing_benefit_net_earnings: 5000
+        carer_premium: 0
+        working_tax_credit: 0
+        WTC_disabled_element: 0
+        WTC_severely_disabled_element: 0
+      non_dependant:
+        members: [adult_non_dependant]
+        housing_benefit_pension_age_regulations_apply: false
+        housing_benefit_net_earnings: 0
+        disability_premium: 0
+        severe_disability_premium: 0
+        working_tax_credit: 100
+        WTC_disabled_element: 100
+        WTC_severely_disabled_element: 0
+    households:
+      household:
+        members: [claimant, partner, adult_non_dependant]
+        country: NORTHERN_IRELAND
+  output:
+    is_lone_parent: [false, false]
+    is_couple: [true, false]
+    housing_benefit_special_earnings_disregard_eligible: [false, false]
+    housing_benefit_special_earnings_disregard: [520, 0]
+
+- name: NORTHERN_IRELAND qualifying young person's disability receipt does not qualify the pension-age claimant
+  period: 2024
+  input:
+    people:
+      claimant:
+        age: 72
+        is_claimant_or_partner: true
+        pip_m: 0
+      qualifying_young_person:
+        age: 18
+        is_claimant_or_partner: false
+        is_in_non_advanced_education: true
+        pip_m: 100
+    benunits:
+      family:
+        members: [claimant, qualifying_young_person]
+        housing_benefit_pension_age_regulations_apply: true
+        housing_benefit_net_earnings: 5000
+        carer_premium: 0
+        working_tax_credit: 0
+        # Isolate receipt scoping from the independent lone-parent route.
+        is_lone_parent: false
+    households:
+      household:
+        members: [claimant, qualifying_young_person]
+        country: NORTHERN_IRELAND
+  output:
+    is_couple: false
+    housing_benefit_special_earnings_disregard_eligible: false
+    housing_benefit_special_earnings_disregard: 260
+
 - name: Standard replacement, lone-parent precedence and earnings cap
   period: 2024
   input:
@@ -62,6 +332,7 @@
     meets_housing_benefit_additional_earnings_disregard_conditions: [false, false, false, false, false, false]
     housing_benefit_on_passporting_benefit: [false, false, false, false, false, false]
   output:
+    housing_benefit_special_earnings_disregard: [1040, 1040, 1300, 500, 260, 520]
     housing_benefit_applicable_income_disregard: [1040, 1040, 1300, 500, 260, 520]
 
 - name: Special standard amount participates in additional-disregard threshold
diff --git a/policyengine_uk/variables/gov/dwp/housing_benefit/applicable_income/housing_benefit_special_earnings_disregard_eligible.py b/policyengine_uk/variables/gov/dwp/housing_benefit/applicable_income/housing_benefit_special_earnings_disregard_eligible.py
index 5c15427da6..0eafd1c2e3 100644
--- a/policyengine_uk/variables/gov/dwp/housing_benefit/applicable_income/housing_benefit_special_earnings_disregard_eligible.py
+++ b/policyengine_uk/variables/gov/dwp/housing_benefit/applicable_income/housing_benefit_special_earnings_disregard_eligible.py
@@ -2,6 +2,36 @@
 
 
 class housing_benefit_special_earnings_disregard_eligible(Variable):
+    """Implement the modelled pension-age paragraph 5 qualifying routes.
+
+    GB SI 2006/214 Sch. 4 and NI SR 2006/406 Sch. 5 para. 5(1)(a)
+    list the following receipts implemented here:
+    (ii) "severe disablement allowance under section 68 of the Act";
+    (iii) "attendance allowance";
+    (iv) "disability living allowance under sections 71 to 76 of the Act";
+    (vi) "the disability element or the severe disability element of working
+    tax credit"; and (viii) "personal independence payment".
+    GB (ix) and NI (iva) list "armed forces independence payment".
+    Para. 5(1)(b) adds those "certified as severely sight impaired or blind
+    by a consultant ophthalmologist", represented here by is_blind.
+
+    Only claimant/partner receipts qualify. Working Tax Credit and its
+    disability elements are benefit-unit variables whose formulas scope
+    entitlement to the claimant/partner; a positive element alone does not
+    establish receipt of the award.
+
+    Not derived: long-term Incapacity Benefit (5(1)(a)(i)), prescribed war
+    pension/personal injury mobility supplements (v), main-phase ESA (vii),
+    continuous incapacity for 196 days if terminally ill or 364 days otherwise
+    (5(1)(c)), assessed LCW/LCWRA or the specified assessment-phase exceptions
+    (5(1)(d)), and protected earlier HB awards with eight-week continuity
+    (5(2)-(3)). Pension age disability payment, Scottish adult disability
+    living allowance and adult disability payment also lack dedicated
+    variables here; their upstream mapping to AA/DLA/PIP is not verified.
+    These residual routes require pre-assessed eligibility. Existing benefit
+    qualification approximations are inherited.
+    """
+
     value_type = bool
     entity = BenUnit
     definition_period = YEAR
@@ -37,6 +67,7 @@ def formula(benunit, period, parameters):
                 person,
                 period,
                 [
+                    "sda",
                     "attendance_allowance",
                     "dla_sc",
                     "dla_m",
@@ -47,10 +78,24 @@ def formula(benunit, period, parameters):
             )
             > 0
         )
-        pension = benunit.any(
-            person("is_claimant_or_partner", period)
-            & (qualifying_receipt | person("is_blind", period))
-        ) | (benunit("carer_premium", period) > 0)
+        # Para. 5(1)(a)(vi), as in Pension Credit: disability-related WTC
+        # requires an actual award as well as a positive disability element.
+        wtc_disability_element = (
+            add(
+                benunit,
+                period,
+                ["WTC_disabled_element", "WTC_severely_disabled_element"],
+            )
+            > 0
+        ) & (benunit("working_tax_credit", period) > 0)
+        pension = (
+            benunit.any(
+                person("is_claimant_or_partner", period)
+                & (qualifying_receipt | person("is_blind", period))
+            )
+            | wtc_disability_element
+            | (benunit("carer_premium", period) > 0)
+        )
         # Working-age carer/occupation routes restrict which person's/job's
         # earnings may be disregarded. Do not automatically apply £20 to an
         # ordinary earner solely because their non-earning partner cares.

From 042260687fb98bd075e2b96dae8677c7eea302a1 Mon Sep 17 00:00:00 2001
From: Max Ghenis <mghenis@gmail.com>
Date: Sun, 25 Oct 2026 01:24:46 -0400
Subject: [PATCH 5/7] Repair the cross-module HB disregard property oracle

Apply lone-parent and special precedence and pin the 18/34 couple and disabled single regressions with explicit roles inherited from main.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
---
 ...pensioner_earnings_disregard_properties.py | 59 +++++++++++++++++--
 1 file changed, 53 insertions(+), 6 deletions(-)

diff --git a/policyengine_uk/tests/test_council_tax_reduction_pensioner_earnings_disregard_properties.py b/policyengine_uk/tests/test_council_tax_reduction_pensioner_earnings_disregard_properties.py
index 922a844d15..95473e8c7f 100644
--- a/policyengine_uk/tests/test_council_tax_reduction_pensioner_earnings_disregard_properties.py
+++ b/policyengine_uk/tests/test_council_tax_reduction_pensioner_earnings_disregard_properties.py
@@ -31,16 +31,18 @@
    Benefit's additional sum was £37.10 (SI 2020/371 reg 5) and CTR's stayed
    £17.10 (an intended difference, which the test pins).
 6. The Housing Benefit disregard (#1908) is the statutory weekly sum x 52 in
-   every year from 2015 to 2030, at working and pension age: £5, £10 or £25
-   (SI 2006/213 Sch 4 paras 4, 7, 10; SI 2006/214 Sch 4 paras 2, 7), plus
-   £17.10 (£37.10 in 2020, SI 2020/371 reg 5) where a work condition holds,
+   every year from 2015 to 2030, at working and pension age: £25 for a lone
+   parent, otherwise £20 for a special-qualifying family, otherwise £10 for
+   a couple or £5 for a single claimant (SI 2006/213 Sch 4; SI 2006/214
+   Sch 4), plus £17.10 (£37.10 in 2020, SI 2020/371 reg 5) where a work
+   condition holds,
    for families with enough earnings and on none of Universal Credit, Income
    Support, income-based JSA or income-related ESA (whose working-age
    earnings are all disregarded, Sch 4 para 12).
 """
 
 import numpy as np
-from hypothesis import HealthCheck, given, settings
+from hypothesis import HealthCheck, example, given, settings
 from hypothesis import strategies as st
 
 from policyengine_uk import Simulation
@@ -306,16 +308,61 @@ def test_differential_against_the_housing_benefit_pension_age_disregard(units, y
     ),
     st.integers(2015, 2030),
 )
+@example(
+    units=[
+        dict(
+            shape="couple",
+            nation="ENGLAND",
+            adults=[
+                dict(
+                    age=age,
+                    employment_income=20_000.0,
+                    weekly_hours=0.0,
+                    disabled=False,
+                    state_pension=0.0,
+                )
+                for age in (18, 34)
+            ],
+            children=[],
+        ),
+        dict(
+            shape="single",
+            nation="ENGLAND",
+            adults=[
+                dict(
+                    age=40,
+                    employment_income=20_000.0,
+                    weekly_hours=0.0,
+                    disabled=True,
+                    state_pension=0.0,
+                )
+            ],
+            children=[],
+        ),
+    ],
+    year=2026,
+)
 def test_housing_benefit_disregard_is_the_statutory_weekly_sum_in_every_year(
     units, year
 ):
-    values = calculate(units, year=year, no_income_related_benefits=True)
+    values = calculate(
+        units,
+        year=year,
+        variables=VARIABLES + ["housing_benefit_special_earnings_disregard_eligible"],
+        no_income_related_benefits=True,
+    )
     disregard = values["housing_benefit_applicable_income_disregard"]
     conditions = values[
         "meets_housing_benefit_additional_earnings_disregard_conditions"
     ].astype(bool)
+    special = values["housing_benefit_special_earnings_disregard_eligible"].astype(bool)
     for i, unit in enumerate(units):
-        weekly = WEEKLY[unit["shape"]]
+        if unit["shape"] == "lone_parent":
+            weekly = 25
+        elif special[i]:
+            weekly = 20
+        else:
+            weekly = WEEKLY[unit["shape"]]
         if conditions[i]:
             weekly += 37.1 if year == 2020 else 17.1
         assert abs(disregard[i] - weekly * WEEKS) < 0.01, (unit, year)

From 1db09c3e86b670b44aa35775de71b40d20918c55 Mon Sep 17 00:00:00 2001
From: Max Ghenis <mghenis@gmail.com>
Date: Sun, 25 Oct 2026 01:24:47 -0400
Subject: [PATCH 6/7] Strengthen HB standard cap and age comparison properties

Test every family with eligibility held false and true, independently assert natural eligibility, freeze the special amount, and check selected-standard bounds and statutory precedence.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
---
 ...g_benefit_earnings_disregard_properties.py | 152 +++++++++++++++---
 1 file changed, 131 insertions(+), 21 deletions(-)

diff --git a/policyengine_uk/tests/test_housing_benefit_earnings_disregard_properties.py b/policyengine_uk/tests/test_housing_benefit_earnings_disregard_properties.py
index a79e88531b..475723401e 100644
--- a/policyengine_uk/tests/test_housing_benefit_earnings_disregard_properties.py
+++ b/policyengine_uk/tests/test_housing_benefit_earnings_disregard_properties.py
@@ -22,20 +22,14 @@
    £37.10 (an intended difference).
 5. The disregard reduces applicable income by no more than the claimant's
    and partner's gross earnings, and never raises it.
-6. Metamorphic: the pension-age and working-age schedules agree. Moving every
-   adult between working age (25 to 60) and pension age (67 to 90), with
-   earnings below the tax and National Insurance thresholds, leaves the
-   disregard unchanged. It covers only those earnings and adults aged 25 or
-   over, where nothing age-dependent (para 12, the age-25 test, National
-   Insurance above State Pension age) can differ between the two groups, so
-   it pins the current behaviour rather than independently testing the two
-   schedules. Intended difference: the £20 special disregard has different
-   conditions at each age. At working age it follows the disability premium,
-   which the model grants on the disability flag the draws set; at pension age
-   it needs receipt of a listed benefit, blindness or the carer premium (SI
-   2006/214 Sch 4 paras 4 and 5), none of which the draws supply. The
-   comparison therefore covers families whose special eligibility is the same
-   at both ages, which includes every family without a disabled adult.
+6. Metamorphic: with special eligibility fixed identically false or true,
+   moving every adult between working age (25 to 60) and pension age (67 to
+   90) leaves every family's disregard unchanged. Earnings stay below the
+   tax and National Insurance thresholds and every adult stays over 25.
+   Natural eligibility is checked independently: the disability flag qualifies
+   at working age, but the draws supply no pension-age qualifying receipt,
+   blindness or carer premium (SI 2006/214 Sch 4 paras 4 and 5). Lone parents
+   naturally keep the same £25 even when these eligibility flags differ.
 7. Differential against the old flat formula (£5/£10/£25 by family type, plus
    £37.10 for summed hours over 30, or 16 for lone parents), read without
    CPI uprating. They agree for families whose net earnings cover the flat
@@ -45,6 +39,10 @@
    must differ where net earnings fall below the flat amount (the new
    disregard is the net earnings) and for families without earnings (the new
    disregard is zero).
+8. The selected standard is min(net earnings, 52 times the statutory weekly
+   choice), with £25 lone-parent precedence, then £20 special, then £10
+   couple, then £5 single. These amounts never stack and the selected
+   standard stays between zero and net earnings.
 
 Para 12 is tested on its own: with Income Support, every family has all its
 net earnings disregarded, at working or pension age. Leaving Income Support can
@@ -57,7 +55,7 @@
 """
 
 import numpy as np
-from hypothesis import HealthCheck, given, settings
+from hypothesis import HealthCheck, example, given, settings
 from hypothesis import strategies as st
 
 from policyengine_uk import Simulation
@@ -179,8 +177,14 @@ def situation(units, earnings_bump=0.0, income_support=0.0, age_map=None):
 ]
 
 
-def calculate(units, **kwargs):
+def calculate(units, special_eligible=None, **kwargs):
     sim = Simulation(situation=situation(units, **kwargs))
+    if special_eligible is not None:
+        sim.set_input(
+            "housing_benefit_special_earnings_disregard_eligible",
+            YEAR,
+            np.full(len(units), special_eligible),
+        )
     return {v: np.asarray(sim.calculate(v, YEAR), dtype=float) for v in VARIABLES}
 
 
@@ -229,6 +233,7 @@ def test_weekly_amounts_are_frozen_from_2015_to_2030():
     for year in range(2015, 2031):
         p = system.parameters(year).gov.dwp.housing_benefit.means_test.income_disregard
         assert (p.single, p.couple, p.lone_parent) == (5, 10, 25), year
+        assert p.special == 20, year
         # SI 2020/371 reg 5: £37.10 from 6 April 2020 to 4 April 2021, which
         # the model's fiscal-year convention reads as 2020.
         expected_worker = 37.1 if year == 2020 else 17.1
@@ -258,19 +263,124 @@ def test_disregard_lowers_applicable_income_by_no_more_than_earnings(units):
         min_size=1,
     )
 )
+@example(
+    units=[
+        dict(
+            shape=shape,
+            adults=[
+                dict(
+                    age=40,
+                    employment_income=2_000.0,
+                    weekly_hours=0.0,
+                    disabled=True,
+                    pension_contributions=0.0,
+                )
+                for _ in range(n_adults)
+            ],
+            children=[5] * n_children,
+            childcare=0.0,
+        )
+        for shape, (n_adults, n_children) in SHAPES.items()
+    ]
+)
 def test_pension_age_and_working_age_schedules_agree(units):
     working_age = calculate(units)
+
     # Map 25-60 onto 67-90, keeping everyone at or over 25.
-    pension_age = calculate(units, age_map=lambda age: 67 + (age - 25) * 23 // 35)
+    def pension_age_map(age):
+        return 67 + (age - 25) * 23 // 35
+
+    pension_age = calculate(units, age_map=pension_age_map)
     key = "housing_benefit_applicable_income_disregard"
     special = "housing_benefit_special_earnings_disregard_eligible"
     for i, unit in enumerate(units):
-        if not any(adult["disabled"] for adult in unit["adults"]):
-            # Nothing else in the draws can make the two routes differ.
-            assert working_age[special][i] == pension_age[special][i], unit
-        if working_age[special][i] == pension_age[special][i]:
+        assert working_age[special][i] == any(
+            adult["disabled"] for adult in unit["adults"]
+        ), unit
+        assert not pension_age[special][i], unit
+        if unit["shape"] == "lone_parent":
             assert abs(working_age[key][i] - pension_age[key][i]) < 0.01, unit
 
+    for eligible in (False, True):
+        working_age_fixed = calculate(units, special_eligible=eligible)
+        pension_age_fixed = calculate(
+            units, special_eligible=eligible, age_map=pension_age_map
+        )
+        for i, unit in enumerate(units):
+            assert working_age_fixed[special][i] == eligible, unit
+            assert pension_age_fixed[special][i] == eligible, unit
+            assert abs(working_age_fixed[key][i] - pension_age_fixed[key][i]) < 0.01, (
+                unit,
+                eligible,
+            )
+
+
+@PROPERTY_SETTINGS
+@given(
+    st.lists(
+        st.tuples(
+            st.sampled_from(sorted(SHAPES)),
+            st.integers(0, 100_000_000).map(lambda pennies: pennies / 100),
+            st.booleans(),
+        ),
+        min_size=1,
+        max_size=30,
+    )
+)
+@example(
+    cases=[
+        (shape, net, eligible)
+        for shape in SHAPES
+        for net in (0, 259.99, 260, 500, 520, 1039.99, 1040, 1300, 2000)
+        for eligible in (False, True)
+    ]
+)
+def test_selected_standard_has_statutory_precedence_and_is_capped_at_net_earnings(
+    cases,
+):
+    units = []
+    for shape, _, _ in cases:
+        n_adults, n_children = SHAPES[shape]
+        units.append(
+            dict(
+                shape=shape,
+                adults=[
+                    dict(
+                        age=40,
+                        employment_income=0.0,
+                        weekly_hours=0.0,
+                        disabled=False,
+                        pension_contributions=0.0,
+                    )
+                    for _ in range(n_adults)
+                ],
+                children=[5] * n_children,
+                childcare=0.0,
+            )
+        )
+    sim = Simulation(situation=situation(units))
+    # Supply net earnings independently of taxes, pensions and gross income:
+    # this property tests the selected standard before downstream composition.
+    sim.set_input("housing_benefit_net_earnings", YEAR, [case[1] for case in cases])
+    sim.set_input(
+        "housing_benefit_special_earnings_disregard_eligible",
+        YEAR,
+        [case[2] for case in cases],
+    )
+    selected = sim.calculate("housing_benefit_special_earnings_disregard", YEAR)
+    net_earnings = sim.calculate("housing_benefit_net_earnings", YEAR)
+    for actual, net, (shape, _, eligible) in zip(selected, net_earnings, cases):
+        if shape == "lone_parent":
+            weekly = 25
+        elif eligible:
+            weekly = 20
+        elif SHAPES[shape][0] == 2:
+            weekly = 10
+        else:
+            weekly = 5
+        assert actual == min(net, WEEKS * weekly), (shape, net, eligible)
+        assert 0 <= actual <= net, (shape, net, eligible)
+
 
 @PROPERTY_SETTINGS
 @given(st.lists(families(), min_size=1, max_size=30))

From 05246aa1da7df24ffde0c6b40b7ce5bef4f22ef7 Mon Sep 17 00:00:00 2001
From: Max Ghenis <mghenis@gmail.com>
Date: Sun, 25 Oct 2026 05:00:42 -0400
Subject: [PATCH 7/7] Pin the working-age special disregard for a disabled
 single
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

The cross-module property reads special eligibility from the model, so a
regression that made a disabled working-age single ineligible would
still pass it. A deterministic test now asserts eligibility and the
£1,040 standard directly (no hours, so no additional sum; tax credits
have ended by 2026, so the working tax credit route is off). The
eligibility docstring now names the working-age premium route too, and
the Housing Benefit property docstring notes that its pension-age
"not special" check relies on YEAR falling after tax credits end.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
---
 ...pensioner_earnings_disregard_properties.py | 29 +++++++++++++++++++
 ...g_benefit_earnings_disregard_properties.py |  5 +++-
 ...fit_special_earnings_disregard_eligible.py |  3 +-
 3 files changed, 35 insertions(+), 2 deletions(-)

diff --git a/policyengine_uk/tests/test_council_tax_reduction_pensioner_earnings_disregard_properties.py b/policyengine_uk/tests/test_council_tax_reduction_pensioner_earnings_disregard_properties.py
index 95473e8c7f..c40751e943 100644
--- a/policyengine_uk/tests/test_council_tax_reduction_pensioner_earnings_disregard_properties.py
+++ b/policyengine_uk/tests/test_council_tax_reduction_pensioner_earnings_disregard_properties.py
@@ -366,3 +366,32 @@ def test_housing_benefit_disregard_is_the_statutory_weekly_sum_in_every_year(
         if conditions[i]:
             weekly += 37.1 if year == 2020 else 17.1
         assert abs(disregard[i] - weekly * WEEKS) < 0.01, (unit, year)
+
+
+def test_disabled_working_age_single_gets_the_special_hb_disregard():
+    # The property above reads special eligibility from the model, so pin it
+    # here. With no hours the additional sum cannot apply, and tax credits
+    # have ended by 2026, so the working tax credit route is off.
+    unit = dict(
+        shape="single",
+        nation="ENGLAND",
+        children=[],
+        adults=[
+            dict(
+                age=40,
+                employment_income=20_000.0,
+                weekly_hours=0.0,
+                disabled=True,
+                state_pension=0.0,
+            )
+        ],
+    )
+    values = calculate(
+        [unit],
+        year=2026,
+        variables=VARIABLES + ["housing_benefit_special_earnings_disregard_eligible"],
+        no_income_related_benefits=True,
+    )
+    assert values["housing_benefit_special_earnings_disregard_eligible"][0]
+    disregard = values["housing_benefit_applicable_income_disregard"][0]
+    assert abs(disregard - 20 * WEEKS) < 0.01
diff --git a/policyengine_uk/tests/test_housing_benefit_earnings_disregard_properties.py b/policyengine_uk/tests/test_housing_benefit_earnings_disregard_properties.py
index 475723401e..ce2b185f9e 100644
--- a/policyengine_uk/tests/test_housing_benefit_earnings_disregard_properties.py
+++ b/policyengine_uk/tests/test_housing_benefit_earnings_disregard_properties.py
@@ -28,7 +28,10 @@
    tax and National Insurance thresholds and every adult stays over 25.
    Natural eligibility is checked independently: the disability flag qualifies
    at working age, but the draws supply no pension-age qualifying receipt,
-   blindness or carer premium (SI 2006/214 Sch 4 paras 4 and 5). Lone parents
+   blindness or carer premium (SI 2006/214 Sch 4 paras 4 and 5), and YEAR
+   falls after tax credits end in the model (6 April 2025, tax_credits.active),
+   so the disability-element route of working tax credit cannot apply. A YEAR
+   before 2025-26 would need that route excluded from the draws. Lone parents
    naturally keep the same £25 even when these eligibility flags differ.
 7. Differential against the old flat formula (£5/£10/£25 by family type, plus
    £37.10 for summed hours over 30, or 16 for lone parents), read without
diff --git a/policyengine_uk/variables/gov/dwp/housing_benefit/applicable_income/housing_benefit_special_earnings_disregard_eligible.py b/policyengine_uk/variables/gov/dwp/housing_benefit/applicable_income/housing_benefit_special_earnings_disregard_eligible.py
index 0eafd1c2e3..f1735a222f 100644
--- a/policyengine_uk/variables/gov/dwp/housing_benefit/applicable_income/housing_benefit_special_earnings_disregard_eligible.py
+++ b/policyengine_uk/variables/gov/dwp/housing_benefit/applicable_income/housing_benefit_special_earnings_disregard_eligible.py
@@ -2,7 +2,8 @@
 
 
 class housing_benefit_special_earnings_disregard_eligible(Variable):
-    """Implement the modelled pension-age paragraph 5 qualifying routes.
+    """Implement the working-age premium route and the modelled pension-age
+    paragraph 5 qualifying routes.
 
     GB SI 2006/214 Sch. 4 and NI SR 2006/406 Sch. 5 para. 5(1)(a)
     list the following receipts implemented here: