Count Incapacity Benefit and SDA as Universal Credit unearned income (UC transitional regulations reg. 25) #2424

What's wrong

gov.dwp.universal_credit.means_test.income_definitions.unearned (the list behind uc_unearned_income) leaves out Incapacity Benefit and Severe Disablement Allowance. The Universal Credit (Transitional Provisions) Regulations 2014 (SI 2014/1230) reg. 25(1) says that where an award of Universal Credit is made to a claimant entitled to either benefit, regulation 66 of the Universal Credit Regulations 2013 applies as if that benefit were added to the descriptions of unearned income in paragraph (1)(b).

• Law: https://www.legislation.gov.uk/uksi/2014/1230/regulation/25
• Reg. 66(1)(b), which the list follows today: https://www.legislation.gov.uk/uksi/2013/376/regulation/66

How it shows up

The aggregate-impact counted-once guard (#2335) raises incapacity_benefit by £1 per person in 2026. Universal Credit then rises one for one in 72 households, and only through Carer's Allowance:

• Incapacity Benefit overlaps Carer's Allowance (gov.dwp.carers_allowance.overlapping_benefits), so Carer's Allowance falls.
• Universal Credit counts Carer's Allowance as unearned income but not Incapacity Benefit, so it rises by what Carer's Allowance lost.

Under reg. 25(1) the two moves would cancel, and Universal Credit would not change.

Size

On the certified dataset (uk-data 1.58.1, policyengine-uk 2.132.6):

• incapacity_benefit is £0 in 2026 and 2029.
• sda totals £27.1m in 2026 and £29.2m in 2029.
• Fewer than 10 records are Universal Credit claimants with an award and SDA.

The fiscal effect of the fix is therefore expected to be negligible. It has not been measured; a real run should come with the fix.

Fix

Add incapacity_benefit and sda to the unearned income list, effective from 16 June 2014 (the regulations' commencement), and to the 2023-11-19 entry. Add YAML tests:

• a claimant with Carer's Allowance and Incapacity Benefit, whose Universal Credit is unchanged by the overlap;
• a claimant with SDA.

Mirror the change in rulespec-uk per the parity rule.