diff --git a/openapi/api.yaml b/openapi/api.yaml
index d03de760..eb21fc3f 100644
--- a/openapi/api.yaml
+++ b/openapi/api.yaml
@@ -9245,7 +9245,6 @@ paths:
       description: Apply credit payment to the outstanding balance on an existing
         charge invoice from an account’s available balance from existing credit invoices.
       parameters:
-      - "$ref": "#/components/parameters/site_id"
       - "$ref": "#/components/parameters/invoice_id"
       responses:
         '200':
@@ -18621,7 +18620,7 @@ components:
           type: string
           maxLength: 20
           description: Code that represents a geographic entity (location or object).
-            Only returned for Sling Vertex Integration
+            Only returned when Vertex or Avalara for Communications is enabled.
     AddressWithName:
       allOf:
       - "$ref": "#/components/schemas/Address"
@@ -20195,6 +20194,19 @@ components:
           description: Any values that resemble a credit card number or security code
             (CVV/CVC) will be rejected.
           maxLength: 255
+        source_record_type:
+          type: string
+          title: Source record type
+          description: The type of record this custom field was automatically copied
+            from. Only present when the field was copied from another record.
+          readOnly: true
+          "$ref": "#/components/schemas/SourceRecordTypeEnum"
+        source_record_id:
+          type: string
+          title: Source record ID
+          description: The UUID of the record this custom field was automatically
+            copied from. Only present when the field was copied from another record.
+          readOnly: true
       required:
       - name
       - value
@@ -20206,6 +20218,15 @@ components:
         remove a field send the name with a null or empty value.
       items:
         "$ref": "#/components/schemas/CustomField"
+    InvoiceCustomFields:
+      type: array
+      title: Custom fields
+      description: A list of custom fields that were on the account at the time of
+        invoice creation and were marked to be displayed on invoices. Read-only; cannot
+        be set directly on the invoice.
+      readOnly: true
+      items:
+        "$ref": "#/components/schemas/CustomField"
     CustomFieldDefinition:
       type: object
       title: Custom field definition
@@ -21084,6 +21105,8 @@ components:
           title: Business Entity ID
           description: Unique ID to identify the business entity assigned to the invoice.
             Available when the `Multiple Business Entities` feature is enabled.
+        custom_fields:
+          "$ref": "#/components/schemas/InvoiceCustomFields"
     InvoiceCreate:
       type: object
       properties:
@@ -22735,7 +22758,7 @@ components:
           type: string
           maxLength: 20
           description: Code that represents a geographic entity (location or object).
-            Only returned for Sling Vertex Integration
+            Only returned when Vertex or Avalara for Communications is enabled.
         created_at:
           type: string
           title: Created at
@@ -22823,7 +22846,7 @@ components:
           type: string
           maxLength: 20
           description: Code that represents a geographic entity (location or object).
-            Only returned for Sling Vertex Integration
+            Only returned when Vertex or Avalara for Communications is enabled.
         country:
           type: string
           maxLength: 50
@@ -23154,7 +23177,7 @@ components:
           type: string
           maxLength: 20
           description: Code that represents a geographic entity (location or object).
-            Only returned for Sling Vertex Integration
+            Only returned when Vertex or Avalara for Communications is enabled.
     Site:
       type: object
       properties:
@@ -28104,3 +28127,11 @@ components:
       enum:
       - customer
       - merchant
+    SourceRecordTypeEnum:
+      type: string
+      description: The type of record a custom field was automatically copied from.
+      enum:
+      - account
+      - plan
+      - product
+      - subscription
diff --git a/recurly/resources.py b/recurly/resources.py
index ae812fa7..84df444c 100644
--- a/recurly/resources.py
+++ b/recurly/resources.py
@@ -56,7 +56,7 @@ class Address(Resource):
     country : str
         Country, 2-letter ISO 3166-1 alpha-2 code.
     geo_code : str
-        Code that represents a geographic entity (location or object). Only returned for Sling Vertex Integration
+        Code that represents a geographic entity (location or object). Only returned when Vertex or Avalara for Communications is enabled.
     phone : str
         Phone number
     postal_code : str
@@ -251,7 +251,7 @@ class ShippingAddress(Resource):
     email : str
     first_name : str
     geo_code : str
-        Code that represents a geographic entity (location or object). Only returned for Sling Vertex Integration
+        Code that represents a geographic entity (location or object). Only returned when Vertex or Avalara for Communications is enabled.
     id : str
         Shipping Address ID
     last_name : str
@@ -508,12 +508,18 @@ class CustomField(Resource):
     ----------
     name : str
         Fields must be created in the UI before values can be assigned to them.
+    source_record_id : str
+        The UUID of the record this custom field was automatically copied from. Only present when the field was copied from another record.
+    source_record_type : str
+        The type of record this custom field was automatically copied from. Only present when the field was copied from another record.
     value : str
         Any values that resemble a credit card number or security code (CVV/CVC) will be rejected.
     """
 
     schema = {
         "name": str,
+        "source_record_id": str,
+        "source_record_type": str,
         "value": str,
     }
 
@@ -943,7 +949,7 @@ class AddressWithName(Resource):
     first_name : str
         First name
     geo_code : str
-        Code that represents a geographic entity (location or object). Only returned for Sling Vertex Integration
+        Code that represents a geographic entity (location or object). Only returned when Vertex or Avalara for Communications is enabled.
     last_name : str
         Last name
     phone : str
@@ -1568,6 +1574,8 @@ class Invoice(Resource):
         Credit payments
     currency : str
         3-letter ISO 4217 currency code.
+    custom_fields : :obj:`list` of :obj:`CustomField`
+        A list of custom fields that were on the account at the time of invoice creation and were marked to be displayed on invoices. Read-only; cannot be set directly on the invoice.
     customer_notes : str
         This will default to the Customer Notes text specified on the Invoice Settings. Specify custom notes to add or override Customer Notes.
     discount : float
@@ -1667,6 +1675,7 @@ class Invoice(Resource):
         "created_at": datetime,
         "credit_payments": ["CreditPayment"],
         "currency": str,
+        "custom_fields": ["CustomField"],
         "customer_notes": str,
         "discount": float,
         "due_at": datetime,
@@ -1718,7 +1727,7 @@ class InvoiceAddress(Resource):
     first_name : str
         First name
     geo_code : str
-        Code that represents a geographic entity (location or object). Only returned for Sling Vertex Integration
+        Code that represents a geographic entity (location or object). Only returned when Vertex or Avalara for Communications is enabled.
     last_name : str
         Last name
     name_on_account : str