diff --git a/changelog.d/1914.fixed.md b/changelog.d/1914.fixed.md
new file mode 100644
index 0000000000..3f184fc988
--- /dev/null
+++ b/changelog.d/1914.fixed.md
@@ -0,0 +1 @@
+Income-related ESA ends for the claimant and partner of a family that claims Universal Credit, as the claim brings its abolition into force (Welfare Reform Act 2012 s.33(1)(b); SI 2013/983 art. 4), so it is no longer paid alongside Universal Credit (#1914).
diff --git a/policyengine_uk/tests/policy/baseline/finance/benefit/family/esa_income/esa_income_capital.yaml b/policyengine_uk/tests/policy/baseline/finance/benefit/family/esa_income/esa_income_capital.yaml
index aac4fec6c6..87009a36b1 100644
--- a/policyengine_uk/tests/policy/baseline/finance/benefit/family/esa_income/esa_income_capital.yaml
+++ b/policyengine_uk/tests/policy/baseline/finance/benefit/family/esa_income/esa_income_capital.yaml
@@ -9,6 +9,7 @@
     benunits:
       benunit:
         members: claimant
+        would_claim_uc: false
     households:
       household:
         members: claimant
@@ -32,6 +33,7 @@
     benunits:
       benunit:
         members: claimant
+        would_claim_uc: false
     households:
       household:
         members: claimant
@@ -51,6 +53,7 @@
     benunits:
       benunit:
         members: claimant
+        would_claim_uc: false
     households:
       household:
         members: claimant
@@ -71,6 +74,7 @@
     benunits:
       benunit:
         members: claimant
+        would_claim_uc: false
     households:
       household:
         members: claimant
@@ -91,6 +95,7 @@
     benunits:
       benunit:
         members: claimant
+        would_claim_uc: false
     households:
       household:
         members: claimant
@@ -135,6 +140,7 @@
     benunits:
       claimant_benunit:
         members: claimant
+        would_claim_uc: false
       unrelated_benunit:
         members: unrelated_adult
     households:
@@ -158,8 +164,10 @@
     benunits:
       benunit_1:
         members: claimant_1
+        would_claim_uc: false
       benunit_2:
         members: claimant_2
+        would_claim_uc: false
     households:
       household:
         members: [claimant_1, claimant_2]
@@ -182,6 +190,7 @@
       benunit:
         members: [claimant, child]
         would_claim_IS: true
+        would_claim_uc: false
     households:
       household:
         members: [claimant, child]
@@ -202,6 +211,7 @@
     benunits:
       benunit:
         members: claimant
+        would_claim_uc: false
     households:
       household:
         members: claimant
diff --git a/policyengine_uk/tests/policy/baseline/finance/benefit/family/esa_income/esa_income_remunerative_work.yaml b/policyengine_uk/tests/policy/baseline/finance/benefit/family/esa_income/esa_income_remunerative_work.yaml
index c57c401bbf..eacc7e084d 100644
--- a/policyengine_uk/tests/policy/baseline/finance/benefit/family/esa_income/esa_income_remunerative_work.yaml
+++ b/policyengine_uk/tests/policy/baseline/finance/benefit/family/esa_income/esa_income_remunerative_work.yaml
@@ -40,6 +40,7 @@
     benunits:
       benunit:
         members: [claimant]
+        would_claim_uc: false
     households:
       household:
         members: [claimant]
@@ -63,6 +64,7 @@
     benunits:
       benunit:
         members: [claimant]
+        would_claim_uc: false
     households:
       household:
         members: [claimant]
@@ -88,6 +90,7 @@
     benunits:
       benunit:
         members: [claimant]
+        would_claim_uc: false
     households:
       household:
         members: [claimant]
@@ -112,6 +115,7 @@
     benunits:
       benunit:
         members: [claimant]
+        would_claim_uc: false
     households:
       household:
         members: [claimant]
@@ -135,6 +139,7 @@
     benunits:
       benunit:
         members: [claimant]
+        would_claim_uc: false
     households:
       household:
         members: [claimant]
@@ -159,6 +164,7 @@
     benunits:
       benunit:
         members: [claimant]
+        would_claim_uc: false
     households:
       household:
         members: [claimant]
@@ -181,6 +187,7 @@
     benunits:
       benunit:
         members: [claimant]
+        would_claim_uc: false
     households:
       household:
         members: [claimant]
@@ -205,6 +212,7 @@
     benunits:
       benunit:
         members: [claimant]
+        would_claim_uc: false
     households:
       household:
         members: [claimant]
@@ -226,6 +234,7 @@
     benunits:
       benunit:
         members: [claimant]
+        would_claim_uc: false
     households:
       household:
         members: [claimant]
@@ -248,6 +257,7 @@
     benunits:
       benunit:
         members: [claimant]
+        would_claim_uc: false
     households:
       household:
         members: [claimant]
@@ -275,6 +285,7 @@
     benunits:
       benunit:
         members: [claimant]
+        would_claim_uc: false
     households:
       household:
         members: [claimant]
@@ -299,6 +310,7 @@
     benunits:
       benunit:
         members: [claimant]
+        would_claim_uc: false
     households:
       household:
         members: [claimant]
@@ -320,6 +332,7 @@
     benunits:
       benunit:
         members: [claimant]
+        would_claim_uc: false
     households:
       household:
         members: [claimant]
@@ -348,6 +361,7 @@
     benunits:
       benunit:
         members: [claimant]
+        would_claim_uc: false
     households:
       household:
         members: [claimant]
@@ -383,6 +397,7 @@
     benunits:
       benunit:
         members: [claimant]
+        would_claim_uc: false
     households:
       household:
         members: [claimant]
@@ -410,6 +425,7 @@
     benunits:
       benunit:
         members: [claimant]
+        would_claim_uc: false
     households:
       household:
         members: [claimant]
@@ -433,6 +449,7 @@
     benunits:
       benunit:
         members: [claimant]
+        would_claim_uc: false
     households:
       household:
         members: [claimant]
@@ -458,6 +475,7 @@
     benunits:
       benunit:
         members: [claimant]
+        would_claim_uc: false
     households:
       household:
         members: [claimant]
@@ -483,6 +501,7 @@
     benunits:
       benunit:
         members: [claimant]
+        would_claim_uc: false
     households:
       household:
         members: [claimant]
@@ -514,6 +533,7 @@
     benunits:
       benunit:
         members: [claimant]
+        would_claim_uc: false
     households:
       household:
         members: [claimant]
@@ -540,6 +560,7 @@
     benunits:
       benunit:
         members: [claimant]
+        would_claim_uc: false
     households:
       household:
         members: [claimant]
@@ -571,6 +592,7 @@
     benunits:
       benunit:
         members: [claimant]
+        would_claim_uc: false
     households:
       household:
         members: [claimant]
@@ -596,6 +618,7 @@
     benunits:
       benunit:
         members: [claimant]
+        would_claim_uc: false
     households:
       household:
         members: [claimant]
@@ -620,6 +643,7 @@
     benunits:
       benunit:
         members: [claimant]
+        would_claim_uc: false
     households:
       household:
         members: [claimant]
@@ -646,6 +670,7 @@
     benunits:
       benunit:
         members: [claimant]
+        would_claim_uc: false
     households:
       household:
         members: [claimant]
@@ -678,6 +703,7 @@
     benunits:
       benunit:
         members: [claimant]
+        would_claim_uc: false
     households:
       household:
         members: [claimant]
@@ -703,6 +729,7 @@
     benunits:
       benunit:
         members: [claimant]
+        would_claim_uc: false
     households:
       household:
         members: [claimant]
@@ -734,6 +761,7 @@
     benunits:
       benunit:
         members: [claimant]
+        would_claim_uc: false
     households:
       household:
         members: [claimant]
@@ -760,6 +788,7 @@
     benunits:
       benunit:
         members: [claimant]
+        would_claim_uc: false
     households:
       household:
         members: [claimant]
@@ -791,6 +820,7 @@
     benunits:
       benunit:
         members: [claimant]
+        would_claim_uc: false
     households:
       household:
         members: [claimant]
@@ -818,6 +848,7 @@
     benunits:
       benunit:
         members: [claimant]
+        would_claim_uc: false
     households:
       household:
         members: [claimant]
@@ -843,6 +874,7 @@
     benunits:
       benunit:
         members: [claimant]
+        would_claim_uc: false
     households:
       household:
         members: [claimant]
@@ -868,6 +900,7 @@
     benunits:
       benunit:
         members: [claimant]
+        would_claim_uc: false
     households:
       household:
         members: [claimant]
@@ -899,6 +932,7 @@
     benunits:
       couple:
         members: [claimant, partner]
+        would_claim_uc: false
     households:
       household:
         members: [claimant, partner]
@@ -924,6 +958,7 @@
     benunits:
       couple:
         members: [claimant, partner]
+        would_claim_uc: false
     households:
       household:
         members: [claimant, partner]
@@ -949,6 +984,7 @@
     benunits:
       couple:
         members: [claimant, partner]
+        would_claim_uc: false
     households:
       household:
         members: [claimant, partner]
@@ -975,6 +1011,7 @@
     benunits:
       couple:
         members: [claimant, partner]
+        would_claim_uc: false
     households:
       household:
         members: [claimant, partner]
@@ -1000,6 +1037,7 @@
     benunits:
       couple:
         members: [claimant, partner]
+        would_claim_uc: false
     households:
       household:
         members: [claimant, partner]
@@ -1027,6 +1065,7 @@
     benunits:
       couple:
         members: [first, second]
+        would_claim_uc: false
     households:
       household:
         members: [first, second]
@@ -1053,6 +1092,7 @@
     benunits:
       couple:
         members: [first, second]
+        would_claim_uc: false
     households:
       household:
         members: [first, second]
@@ -1107,6 +1147,7 @@
     benunits:
       benunit:
         members: [claimant, lodger]
+        would_claim_uc: false
     households:
       household:
         members: [claimant, lodger]
@@ -1134,6 +1175,7 @@
     benunits:
       benunit:
         members: [claimant, lodger]
+        would_claim_uc: false
     households:
       household:
         members: [claimant, lodger]
@@ -1167,6 +1209,7 @@
     benunits:
       benunit:
         members: [claimant, lodger]
+        would_claim_uc: false
     households:
       household:
         members: [claimant, lodger]
@@ -1237,6 +1280,7 @@
       couple:
         members: [carer, partner]
         income_support_assessable_capital: 0
+        would_claim_uc: false
     households:
       household:
         members: [carer, partner]
@@ -1268,6 +1312,7 @@
       unit:
         members: [claimant, partner, outside]
         esa_income_assessable_capital: 0
+        would_claim_uc: false
     households:
       household:
         members: [claimant, partner, outside]
diff --git a/policyengine_uk/tests/policy/baseline/finance/benefit/family/esa_income/esa_income_universal_credit_claim.yaml b/policyengine_uk/tests/policy/baseline/finance/benefit/family/esa_income/esa_income_universal_credit_claim.yaml
new file mode 100644
index 0000000000..efddac0f27
--- /dev/null
+++ b/policyengine_uk/tests/policy/baseline/finance/benefit/family/esa_income/esa_income_universal_credit_claim.yaml
@@ -0,0 +1,166 @@
+# Income-related ESA ends when the family claims Universal Credit.
+# A claim for Universal Credit brings the abolition of income-related ESA
+# (Welfare Reform Act 2012 s.33(1)(b)) into force for the claimant's old style
+# ESA award from the first day of the period claimed for, whether or not
+# Universal Credit is awarded (SI 2013/983 art. 4(1), (2)(a), (3)(a) and (9);
+# Northern Ireland: Welfare Reform (NI) Order 2015 art. 39(1)(b) and SR
+# 2017/190 art. 6). The two-week run-on (SI 2019/1152 reg. 5) is not modelled
+# in an annual model. A member who is neither the claimant nor the partner
+# claims in their own right and is not part of the family's claim.
+# No case has capital, so no tariff income: the award is the reported amount.
+
+- name: Case 1, a single claimant who claims Universal Credit loses income-related ESA.
+  period: 2025
+  absolute_error_margin: 0.01
+  input:
+    people:
+      person1:
+        age: 40
+        is_claimant_or_partner: true
+        esa_income_reported: 5_000
+    benunits:
+      benunit:
+        members: [person1]
+        would_claim_uc: true
+    households:
+      household:
+        members: [person1]
+  output:
+    claims_universal_credit: true
+    esa_income_report_closed: true
+    esa_income_eligible: false
+    # The UC claim ends the award: 0, not the 5_000 reported.
+    esa_income: 0
+    claimant_or_partner_esa_income: 0
+    is_on_income_related_esa: false
+
+- name: Case 2, the same claimant without a Universal Credit claim keeps income-related ESA.
+  period: 2025
+  absolute_error_margin: 0.01
+  input:
+    people:
+      person1:
+        age: 40
+        is_claimant_or_partner: true
+        esa_income_reported: 5_000
+    benunits:
+      benunit:
+        members: [person1]
+        would_claim_uc: false
+    households:
+      household:
+        members: [person1]
+  output:
+    claims_universal_credit: false
+    esa_income_report_closed: false
+    esa_income_eligible: true
+    # No claim, no tariff income: the reported 5_000.
+    esa_income: 5_000
+    claimant_or_partner_esa_income: 5_000
+    is_on_income_related_esa: true
+
+- name: Case 3, a Universal Credit claim ends income-related ESA even when no Universal Credit is awarded.
+  period: 2025
+  absolute_error_margin: 0.01
+  input:
+    people:
+      person1:
+        age: 40
+        is_claimant_or_partner: true
+        esa_income_reported: 5_000
+        private_pension_income: 40_000
+    benunits:
+      benunit:
+        members: [person1]
+        would_claim_uc: true
+    households:
+      household:
+        members: [person1]
+  output:
+    claims_universal_credit: true
+    # £40,000 of pension income is UC unearned income above the £4,801.68
+    # 2025-26 standard allowance (12 x £400.14), so nothing is awarded.
+    universal_credit: 0
+    esa_income_report_closed: true
+    # The claim still ends the old style award (art. 4(9) of SI 2013/983).
+    esa_income: 0
+    claimant_or_partner_esa_income: 0
+
+- name: Case 4, the couple's Universal Credit claim leaves a non-dependent adult's own income-related ESA.
+  period: 2025
+  absolute_error_margin: 0.01
+  input:
+    people:
+      person1:
+        age: 40
+        is_claimant_or_partner: true
+        esa_income_reported: 5_000
+      person2:
+        age: 38
+        is_claimant_or_partner: true
+      person3:
+        age: 30
+        is_claimant_or_partner: false
+        current_education: NOT_IN_EDUCATION
+        esa_income_reported: 2_000
+    benunits:
+      benunit:
+        members: [person1, person2, person3]
+        would_claim_uc: true
+    households:
+      household:
+        members: [person1, person2, person3]
+  output:
+    claims_universal_credit: true
+    esa_income_report_closed: [true, true, false]
+    # Only person3's own claim is left, and person3 does not work.
+    esa_income_eligible: true
+    # 2_000, person3's own award, not 5_000 + 2_000.
+    esa_income: 2_000
+    claimant_or_partner_esa_income: 0
+    is_on_income_related_esa: [false, false, true]
+
+- name: Case 5, the gate applies in 2027, after income-related ESA's 1 July 2026 abolition date.
+  period: 2027
+  absolute_error_margin: 0.01
+  input:
+    people:
+      person1:
+        age: 40
+        is_claimant_or_partner: true
+        esa_income_reported: 5_000
+    benunits:
+      benunit:
+        members: [person1]
+        would_claim_uc: true
+    households:
+      household:
+        members: [person1]
+  output:
+    claims_universal_credit: true
+    esa_income_report_closed: true
+    esa_income: 0
+    claimant_or_partner_esa_income: 0
+
+- name: Case 6, a Universal Credit claim ends income-related ESA in Northern Ireland.
+  period: 2025
+  absolute_error_margin: 0.01
+  input:
+    people:
+      person1:
+        age: 40
+        is_claimant_or_partner: true
+        esa_income_reported: 5_000
+    benunits:
+      benunit:
+        members: [person1]
+        would_claim_uc: true
+    households:
+      household:
+        members: [person1]
+        region: NORTHERN_IRELAND
+  output:
+    claims_universal_credit: true
+    esa_income_report_closed: true
+    esa_income: 0
+    claimant_or_partner_esa_income: 0
diff --git a/policyengine_uk/tests/policy/baseline/finance/benefit/family/esa_income/legacy_capital.yaml b/policyengine_uk/tests/policy/baseline/finance/benefit/family/esa_income/legacy_capital.yaml
index beed6513c8..1c37c4c5c4 100644
--- a/policyengine_uk/tests/policy/baseline/finance/benefit/family/esa_income/legacy_capital.yaml
+++ b/policyengine_uk/tests/policy/baseline/finance/benefit/family/esa_income/legacy_capital.yaml
@@ -64,6 +64,7 @@
     benunits:
       claimant_benunit:
         members: [claimant]
+        would_claim_uc: false
       unrelated_benunit:
         members: [unrelated_claimant]
     households:
diff --git a/policyengine_uk/tests/policy/baseline/finance/benefit/family/income_support/income_support_claimant_partner_gates.yaml b/policyengine_uk/tests/policy/baseline/finance/benefit/family/income_support/income_support_claimant_partner_gates.yaml
index 1dc8fa0c6b..5e3e9191f1 100644
--- a/policyengine_uk/tests/policy/baseline/finance/benefit/family/income_support/income_support_claimant_partner_gates.yaml
+++ b/policyengine_uk/tests/policy/baseline/finance/benefit/family/income_support/income_support_claimant_partner_gates.yaml
@@ -519,6 +519,7 @@
         members: [carer, partner]
         income_support_assessable_capital: 0
         esa_income_assessable_capital: 0
+        would_claim_uc: false
   output:
     esa_income: 3_000
     income_support_eligible: false
@@ -542,6 +543,7 @@
         income_support_assessable_capital: 0
         # Above the £16,000 ESA capital limit (ESA Regs 2008 reg 110).
         esa_income_assessable_capital: 20_000
+        would_claim_uc: false
   output:
     esa_income: 0
     income_support_eligible: true
@@ -582,6 +584,7 @@
         members: [carer]
         income_support_assessable_capital: 0
         esa_income: 0
+        would_claim_uc: false
   output:
     # The model pays no income-related ESA, so none bars Income Support.
     income_support_eligible: true
diff --git a/policyengine_uk/tests/policy/baseline/finance/benefit/family/legacy_award_readers/claimant_or_partner_awards.yaml b/policyengine_uk/tests/policy/baseline/finance/benefit/family/legacy_award_readers/claimant_or_partner_awards.yaml
index 06af3598f5..82cb89df67 100644
--- a/policyengine_uk/tests/policy/baseline/finance/benefit/family/legacy_award_readers/claimant_or_partner_awards.yaml
+++ b/policyengine_uk/tests/policy/baseline/finance/benefit/family/legacy_award_readers/claimant_or_partner_awards.yaml
@@ -19,6 +19,7 @@
     benunits:
       benunit:
         members: [claimant]
+        would_claim_uc: false
     households:
       household:
         members: [claimant]
@@ -41,6 +42,7 @@
     benunits:
       benunit:
         members: [claimant, partner]
+        would_claim_uc: false
     households:
       household:
         members: [claimant, partner]
@@ -89,6 +91,7 @@
     benunits:
       benunit:
         members: [claimant, other]
+        would_claim_uc: false
     households:
       household:
         members: [claimant, other]
@@ -111,6 +114,7 @@
     benunits:
       benunit:
         members: [claimant]
+        would_claim_uc: false
     households:
       household:
         members: [claimant]
@@ -155,6 +159,7 @@
       benunit:
         members: [claimant]
         esa_income: 0
+        would_claim_uc: false
     households:
       household:
         members: [claimant]
@@ -362,6 +367,7 @@
       benunit:
         members: [claimant]
         esa_income: 200
+        would_claim_uc: false
     households:
       household:
         members: [claimant]
@@ -385,6 +391,7 @@
       benunit:
         members: [claimant]
         esa_income: 0
+        would_claim_uc: false
     households:
       household:
         members: [claimant]
diff --git a/policyengine_uk/tests/policy/baseline/finance/benefit/family/legacy_award_readers/council_tax_reduction_passports.yaml b/policyengine_uk/tests/policy/baseline/finance/benefit/family/legacy_award_readers/council_tax_reduction_passports.yaml
index 88a4f16cfa..e36da6ed71 100644
--- a/policyengine_uk/tests/policy/baseline/finance/benefit/family/legacy_award_readers/council_tax_reduction_passports.yaml
+++ b/policyengine_uk/tests/policy/baseline/finance/benefit/family/legacy_award_readers/council_tax_reduction_passports.yaml
@@ -36,6 +36,7 @@
     benunits:
       benunit:
         members: [claimant]
+        would_claim_uc: false
     households:
       household:
         members: [claimant]
@@ -187,6 +188,7 @@
       nondep_unit:
         members: [nondep, other]
         universal_credit: 0
+        would_claim_uc: false
     households:
       household:
         members: [applicant, nondep, other]
@@ -217,6 +219,7 @@
       nondep_unit:
         members: [payee, partner]
         universal_credit: 0
+        would_claim_uc: false
     households:
       household:
         members: [applicant, payee, partner]
@@ -254,6 +257,7 @@
       nondep_unit:
         members: [payee, partner]
         universal_credit: 0
+        would_claim_uc: false
     households:
       household:
         members: [applicant, payee, partner]
diff --git a/policyengine_uk/tests/policy/baseline/finance/benefit/family/legacy_award_readers/income_support_take_up_and_person_awards.yaml b/policyengine_uk/tests/policy/baseline/finance/benefit/family/legacy_award_readers/income_support_take_up_and_person_awards.yaml
index 9a9b4e688b..09d946e58f 100644
--- a/policyengine_uk/tests/policy/baseline/finance/benefit/family/legacy_award_readers/income_support_take_up_and_person_awards.yaml
+++ b/policyengine_uk/tests/policy/baseline/finance/benefit/family/legacy_award_readers/income_support_take_up_and_person_awards.yaml
@@ -107,6 +107,7 @@
     benunits:
       benunit:
         members: [claimant, partner, other]
+        would_claim_uc: false
     households:
       household:
         members: [claimant, partner, other]
@@ -148,6 +149,7 @@
     benunits:
       benunit:
         members: [claimant]
+        would_claim_uc: false
     households:
       household:
         members: [claimant]
diff --git a/policyengine_uk/tests/policy/baseline/finance/benefit/family/legacy_award_readers/means_test_income.yaml b/policyengine_uk/tests/policy/baseline/finance/benefit/family/legacy_award_readers/means_test_income.yaml
index 8e4bb2be1a..3b5ed5f49c 100644
--- a/policyengine_uk/tests/policy/baseline/finance/benefit/family/legacy_award_readers/means_test_income.yaml
+++ b/policyengine_uk/tests/policy/baseline/finance/benefit/family/legacy_award_readers/means_test_income.yaml
@@ -118,6 +118,7 @@
       benunit:
         members: [claimant, other]
         universal_credit: 0
+        would_claim_uc: false
     households:
       household:
         members: [claimant, other]
diff --git a/policyengine_uk/tests/policy/baseline/finance/benefit/family/legacy_award_readers/mixed_age_couple_pension_credit_saving.yaml b/policyengine_uk/tests/policy/baseline/finance/benefit/family/legacy_award_readers/mixed_age_couple_pension_credit_saving.yaml
index 93921ebd58..5e3e43c563 100644
--- a/policyengine_uk/tests/policy/baseline/finance/benefit/family/legacy_award_readers/mixed_age_couple_pension_credit_saving.yaml
+++ b/policyengine_uk/tests/policy/baseline/finance/benefit/family/legacy_award_readers/mixed_age_couple_pension_credit_saving.yaml
@@ -78,6 +78,7 @@
       benunit:
         members: [older, younger]
         is_mixed_age_couple: true
+        would_claim_uc: false
     households:
       household:
         members: [older, younger]
diff --git a/policyengine_uk/tests/policy/baseline/finance/benefit/family/legacy_award_readers/passports.yaml b/policyengine_uk/tests/policy/baseline/finance/benefit/family/legacy_award_readers/passports.yaml
index cb78e220ce..63c07bf301 100644
--- a/policyengine_uk/tests/policy/baseline/finance/benefit/family/legacy_award_readers/passports.yaml
+++ b/policyengine_uk/tests/policy/baseline/finance/benefit/family/legacy_award_readers/passports.yaml
@@ -45,6 +45,7 @@
     benunits:
       benunit:
         members: [claimant]
+        would_claim_uc: false
     households:
       household:
         members: [claimant]
@@ -153,6 +154,7 @@
         child_tax_credit: 0
         working_tax_credit: 0
         pension_credit: 0
+        would_claim_uc: false
     households:
       household:
         members: [parent, child, other]
@@ -272,6 +274,7 @@
         meets_child_tax_credit_criteria_for_targeted_childcare_entitlement: false
         working_tax_credit_run_on: false
         extended_childcare_entitlement_eligible: false
+        would_claim_uc: false
     households:
       household:
         members: [parent, child, other]
@@ -382,6 +385,7 @@
       benunit:
         members: [claimant, other]
         working_tax_credit: 0
+        would_claim_uc: false
     households:
       household:
         members: [claimant, other]
@@ -413,6 +417,7 @@
     benunits:
       benunit:
         members: [parent, student]
+        would_claim_uc: false
     households:
       household:
         members: [parent, student]
@@ -459,6 +464,7 @@
     benunits:
       benunit:
         members: [student, partner]
+        would_claim_uc: false
     households:
       household:
         members: [student, partner]
@@ -483,6 +489,7 @@
     benunits:
       benunit:
         members: [student, partner]
+        would_claim_uc: false
     households:
       household:
         members: [student, partner]
diff --git a/policyengine_uk/tests/policy/baseline/finance/benefit/family/legacy_award_readers/pension_credit_earnings_disregard.yaml b/policyengine_uk/tests/policy/baseline/finance/benefit/family/legacy_award_readers/pension_credit_earnings_disregard.yaml
index bca7da11ad..417c6041ab 100644
--- a/policyengine_uk/tests/policy/baseline/finance/benefit/family/legacy_award_readers/pension_credit_earnings_disregard.yaml
+++ b/policyengine_uk/tests/policy/baseline/finance/benefit/family/legacy_award_readers/pension_credit_earnings_disregard.yaml
@@ -85,6 +85,7 @@
     benunits:
       benunit:
         members: [claimant, partner]
+        would_claim_uc: false
     households:
       household:
         members: [claimant, partner]
diff --git a/policyengine_uk/tests/policy/baseline/gov/dfe/bursary_fund_16_to_19/bursary_fund_16_to_19.yaml b/policyengine_uk/tests/policy/baseline/gov/dfe/bursary_fund_16_to_19/bursary_fund_16_to_19.yaml
index 33600f00ac..0cf3e91122 100644
--- a/policyengine_uk/tests/policy/baseline/gov/dfe/bursary_fund_16_to_19/bursary_fund_16_to_19.yaml
+++ b/policyengine_uk/tests/policy/baseline/gov/dfe/bursary_fund_16_to_19/bursary_fund_16_to_19.yaml
@@ -239,6 +239,7 @@
     benunits:
       benunit:
         members: ["student"]
+        would_claim_uc: false
     households:
       household:
         members: ["student"]
diff --git a/policyengine_uk/tests/policy/baseline/gov/dwp/lifetime_isa_capital.yaml b/policyengine_uk/tests/policy/baseline/gov/dwp/lifetime_isa_capital.yaml
index fed93729ca..5f5f0b671d 100644
--- a/policyengine_uk/tests/policy/baseline/gov/dwp/lifetime_isa_capital.yaml
+++ b/policyengine_uk/tests/policy/baseline/gov/dwp/lifetime_isa_capital.yaml
@@ -308,6 +308,7 @@
     benunits:
       parent:
         members: parent
+        would_claim_uc: false
       adult_child:
         members: adult_child
     households:
diff --git a/policyengine_uk/tests/policy/baseline/gov/dwp/universal_credit/person_legacy_benefits_closed.yaml b/policyengine_uk/tests/policy/baseline/gov/dwp/universal_credit/person_legacy_benefits_closed.yaml
index 2f4f43bbfb..352e12a1be 100644
--- a/policyengine_uk/tests/policy/baseline/gov/dwp/universal_credit/person_legacy_benefits_closed.yaml
+++ b/policyengine_uk/tests/policy/baseline/gov/dwp/universal_credit/person_legacy_benefits_closed.yaml
@@ -25,7 +25,8 @@
             "claimant",
             "partner",
             "outside"
-          ]
+          ],
+          "would_claim_uc": false
         }
       },
       "households": {
diff --git a/policyengine_uk/tests/policy/baseline/gov/dwp/winter_fuel_payment/relevant_benefit_receipt.yaml b/policyengine_uk/tests/policy/baseline/gov/dwp/winter_fuel_payment/relevant_benefit_receipt.yaml
index 220b4bbcd5..bfd3411b3e 100644
--- a/policyengine_uk/tests/policy/baseline/gov/dwp/winter_fuel_payment/relevant_benefit_receipt.yaml
+++ b/policyengine_uk/tests/policy/baseline/gov/dwp/winter_fuel_payment/relevant_benefit_receipt.yaml
@@ -1184,6 +1184,7 @@
         jsa_income: 0
         income_support: 0
         universal_credit: 0
+        would_claim_uc: false
     households:
       household:
         members: [pension_credit_payee, partner]
diff --git a/policyengine_uk/tests/test_benefit_cap_specified_benefits_properties.py b/policyengine_uk/tests/test_benefit_cap_specified_benefits_properties.py
index 5b173020fe..f65edc3e71 100644
--- a/policyengine_uk/tests/test_benefit_cap_specified_benefits_properties.py
+++ b/policyengine_uk/tests/test_benefit_cap_specified_benefits_properties.py
@@ -4,7 +4,9 @@
 
 - the claimant or partner receives ESA that includes the support component
   (75F(1)(a); 83(1)(a)), industrial injuries benefit, attendance allowance
-  or an armed forces compensation payment (75F(1)(b)-(d); 83(1)(b)-(e));
+  or an armed forces compensation payment (75F(1)(b)-(d); 83(1)(b)-(e)). A
+  Universal Credit claim ends the couple's income-related ESA (SI 2013/983
+  art. 4), so a claiming family can count only contributory ESA;
 - the claimant, partner or a child or young person they are responsible for
   receives disability living allowance (75F(1)(e); 83(1)(f));
 - the claimant, partner or a young person they are responsible for receives
@@ -279,8 +281,14 @@ def reference_specified_benefit(members, benunit_inputs, scheme):
     young_roles = ("young_person", "sixteen") if scheme == "uc" else ("young_person",)
     young_persons = [m for m in members if m["_role"] in young_roles]
     children = [m for m in members if m["_role"] == "child"]
-    # No capital, so the couple's income-related award is their reports.
-    couple_award = any(m["esa_income_reported"] > 0 for m in claimants)
+    # No capital, so the couple's income-related award is their reports,
+    # unless the family claims Universal Credit: the claim ends it (SI
+    # 2013/983 art. 4; esa_income_report_closed). would_claim_uc defaults to
+    # true.
+    claims_uc = benunit_inputs.get("would_claim_uc", True)
+    couple_award = not claims_uc and any(
+        m["esa_income_reported"] > 0 for m in claimants
+    )
 
     def support_component(m):
         # Supplied, or assumed for anyone with their own allowance.
@@ -398,9 +406,12 @@ def reference_cap(members):
 def capped_family(scheme):
     """30,000 of the scheme's award before the cap and none of the other's;
     the other family-level capped benefits are nil, so the capped total is
-    the award plus whatever the claimant's and partner's own benefits add."""
+    the award plus whatever the claimant's and partner's own benefits add.
+    The family claims Universal Credit exactly when it is on it, so the
+    couple's income-related ESA continues only on Housing Benefit."""
     return {
         **CAPPED_FAMILY,
+        "would_claim_uc": scheme == "uc",
         "universal_credit_pre_benefit_cap": 30_000 if scheme == "uc" else 0,
         "housing_benefit_pre_benefit_cap": 30_000 if scheme == "hb" else 0,
         # This supplied award exercises the cap independently of take-up;
diff --git a/policyengine_uk/tests/test_claimant_or_partner_awards_entered_directly.py b/policyengine_uk/tests/test_claimant_or_partner_awards_entered_directly.py
index 8a1104b6c1..39c805137f 100644
--- a/policyengine_uk/tests/test_claimant_or_partner_awards_entered_directly.py
+++ b/policyengine_uk/tests/test_claimant_or_partner_awards_entered_directly.py
@@ -46,7 +46,11 @@ def family(award):
                     reported: {YEAR: 3_000},
                 },
             },
-            "benunits": {"family": {"members": members}},
+            # Not claiming Universal Credit, which would end the claimant's
+            # income-related ESA (esa_income_report_closed).
+            "benunits": {
+                "family": {"members": members, "would_claim_uc": {YEAR: False}}
+            },
             "households": {"home": {"members": members}},
         }
     )
@@ -154,7 +158,11 @@ def test_the_raw_reported_total_is_read_through_the_reports(award):
                     reported: {YEAR: 3_000},
                 },
             },
-            "benunits": {"family": {"members": members}},
+            # Not claiming Universal Credit, which would end the partner's
+            # income-related ESA (esa_income_report_closed).
+            "benunits": {
+                "family": {"members": members, "would_claim_uc": {YEAR: False}}
+            },
             "households": {"home": {"members": members, "savings": {YEAR: 10_000}}},
         }
     )
diff --git a/policyengine_uk/tests/test_disable_simulated_benefits_benefit_cap.py b/policyengine_uk/tests/test_disable_simulated_benefits_benefit_cap.py
index cf8dbee648..3647f78d50 100644
--- a/policyengine_uk/tests/test_disable_simulated_benefits_benefit_cap.py
+++ b/policyengine_uk/tests/test_disable_simulated_benefits_benefit_cap.py
@@ -234,7 +234,11 @@ def test_a_couple_that_is_not_the_claimant_and_partner_reads_the_stored_award():
                 "claimant": {"age": 40, "esa_income_reported": 3_000},
                 "partner": {"age": 38, "esa_income_reported": 2_000},
             },
-            "benunits": {"couple": {"members": ["claimant", "partner"]}},
+            # Not claiming Universal Credit, which would end the couple's
+            # income-related ESA (esa_income_report_closed).
+            "benunits": {
+                "couple": {"members": ["claimant", "partner"], "would_claim_uc": False}
+            },
             "households": {"home": {"members": ["claimant", "partner"]}},
         }
     )
diff --git a/policyengine_uk/tests/test_esa_income_universal_credit_claim_properties.py b/policyengine_uk/tests/test_esa_income_universal_credit_claim_properties.py
new file mode 100644
index 0000000000..6fc6e412da
--- /dev/null
+++ b/policyengine_uk/tests/test_esa_income_universal_credit_claim_properties.py
@@ -0,0 +1,203 @@
+"""Property-based tests for the end of income-related ESA on a Universal
+Credit claim (#1914).
+
+A claim for Universal Credit brings the abolition of income-related ESA
+(Welfare Reform Act 2012 s.33(1)(b)) into force for the claimant's old style
+ESA award, whether or not Universal Credit is awarded (SI 2013/983 art. 4(1),
+(2)(a), (3)(a) and (9); NI: SR 2017/190 art. 6). The claim is the claimant's
+and partner's. A member who is neither, such as a non-dependent adult, claims
+income-related ESA in their own right and is not part of it.
+
+Invariants, for any generated population of working-age families in 2025
+and 2027 (either side of income-related ESA's 1 July 2026 abolition date,
+which the model does not yet apply) with no other legacy benefit, so none is
+moved off legacy benefits:
+
+1. Exclusive: a family that claims Universal Credit pays its claimant and
+   partner no income-related ESA (claimant_or_partner_esa_income), and
+   neither of them is on it (is_on_income_related_esa). So Universal Credit
+   and the claimant's or partner's income-related ESA are never both paid.
+   Without a claim the gate is inert: esa_income_report_closed is
+   person_legacy_benefits_closed.
+2. Differential: claiming Universal Credit gives the same income-related ESA
+   outcomes (esa_income, claimant_or_partner_esa_income, esa_income_eligible
+   and each member's is_on_income_related_esa) as not claiming with the
+   claimant's and partner's reports removed. Another member's own award is
+   what it would be if the couple had never reported one.
+
+Intended: claiming Universal Credit can raise esa_income. While the claimant
+or partner reports an award, the benefit unit's screen tests only them, and
+another member's report is paid or not with their claim
+(esa_income_eligible). Once the claim ends the couple's award, that member is
+screened on their own claim alone, as invariant 2 says.
+"""
+
+import numpy as np
+import pytest
+from hypothesis import HealthCheck, given, settings
+from hypothesis import strategies as st
+
+from policyengine_uk import Simulation
+
+pytestmark = pytest.mark.usefixtures("cloned_uk_tax_benefit_system")
+
+YEARS = (2025, 2027)
+PROPERTY_SETTINGS = settings(
+    max_examples=10,
+    deadline=None,
+    derandomize=True,
+    suppress_health_check=[HealthCheck.too_slow, HealthCheck.data_too_large],
+)
+WORKING_AGE = st.integers(25, 60)
+# "other" is an adult who is neither the claimant, the partner nor a young
+# person they are responsible for, so they claim in their own right.
+SHAPES = {
+    "single": ["claimant"],
+    "couple": ["claimant", "partner"],
+    "lone_parent": ["claimant", "child"],
+    "single_with_other": ["claimant", "other"],
+    "couple_with_other": ["claimant", "partner", "other"],
+}
+REPORT = st.sampled_from([0.0, 2_000.0, 6_000.0])
+BENUNIT_OUTPUTS = [
+    "esa_income",
+    "claimant_or_partner_esa_income",
+    "esa_income_eligible",
+    "claims_universal_credit",
+    "universal_credit",
+]
+PERSON_OUTPUTS = [
+    "is_on_income_related_esa",
+    "is_claimant_or_partner",
+    "esa_income_report_closed",
+    "person_legacy_benefits_closed",
+]
+
+
+@st.composite
+def families(draw):
+    roles = SHAPES[draw(st.sampled_from(sorted(SHAPES)))]
+    members = []
+    for role in roles:
+        members.append(
+            dict(
+                role=role,
+                age=draw(st.integers(0, 15) if role == "child" else WORKING_AGE),
+                esa_income_reported=0.0 if role == "child" else draw(REPORT),
+                employment_income=(
+                    0.0
+                    if role == "child"
+                    else draw(st.sampled_from([0.0, 0.0, 4_000.0, 20_000.0]))
+                ),
+                weekly_hours=0.0
+                if role == "child"
+                else draw(st.sampled_from([0, 10, 30])),
+            )
+        )
+    return dict(
+        members=members,
+        # Around the £6,000 tariff threshold and £16,000 limit.
+        savings=draw(st.sampled_from([0.0, 7_000.0, 20_000.0])),
+        would_claim_uc=draw(st.booleans()),
+    )
+
+
+def every_year(value):
+    return {year: value for year in YEARS}
+
+
+def situation(units, would_claim_uc=None, drop_couple_reports=False):
+    people, benunits, households = {}, {}, {}
+    for i, unit in enumerate(units):
+        names = []
+        for j, member in enumerate(unit["members"]):
+            name = f"p{i}_{j}"
+            couple = member["role"] in ("claimant", "partner")
+            report = member["esa_income_reported"]
+            if drop_couple_reports and couple:
+                report = 0.0
+            # Set every input for every member, or it stops being an input
+            # for the rest of the simulation.
+            people[name] = {
+                "age": every_year(member["age"]),
+                "is_claimant_or_partner": every_year(couple),
+                "current_education": every_year("NOT_IN_EDUCATION"),
+                "esa_income_reported": every_year(report),
+                "employment_income": every_year(member["employment_income"]),
+                "weekly_hours": every_year(member["weekly_hours"]),
+            }
+            names.append(name)
+        claims = unit["would_claim_uc"] if would_claim_uc is None else would_claim_uc
+        benunits[f"b{i}"] = {
+            "members": names,
+            "would_claim_uc": every_year(claims),
+            "claims_all_entitled_benefits": every_year(False),
+        }
+        households[f"h{i}"] = {
+            "members": names,
+            "savings": every_year(unit["savings"]),
+        }
+    return {"people": people, "benunits": benunits, "households": households}
+
+
+def calculate(units, **kwargs):
+    sim = Simulation(situation=situation(units, **kwargs))
+    return {
+        year: {
+            v: np.asarray(sim.calculate(v, year))
+            for v in BENUNIT_OUTPUTS + PERSON_OUTPUTS
+        }
+        for year in YEARS
+    }
+
+
+def members_of(units):
+    """Each person's benefit unit index, in simulation order."""
+    return np.array([i for i, unit in enumerate(units) for _ in unit["members"]])
+
+
+@PROPERTY_SETTINGS
+@given(st.lists(families(), min_size=1, max_size=12))
+def test_a_universal_credit_claim_ends_the_couples_income_related_esa(units):
+    values = calculate(units)
+    benunit = members_of(units)
+    for year in YEARS:
+        v = values[year]
+        claims = v["claims_universal_credit"].astype(bool)
+        # Nothing here moves a family off legacy benefits, so the claim is
+        # would_claim_uc.
+        assert list(claims) == [unit["would_claim_uc"] for unit in units]
+        assert np.all(v["claimant_or_partner_esa_income"][claims] == 0), year
+        assert not np.any(
+            v["is_on_income_related_esa"].astype(bool)
+            & v["is_claimant_or_partner"].astype(bool)
+            & claims[benunit]
+        ), year
+        paid_uc = v["universal_credit"] > 0
+        assert not np.any(paid_uc & (v["claimant_or_partner_esa_income"] > 0)), year
+        not_claiming = ~claims[benunit]
+        assert np.array_equal(
+            v["esa_income_report_closed"][not_claiming],
+            v["person_legacy_benefits_closed"][not_claiming],
+        ), year
+
+
+@PROPERTY_SETTINGS
+@given(st.lists(families(), min_size=1, max_size=12))
+def test_a_claim_is_the_couple_reporting_no_income_related_esa(units):
+    claiming = calculate(units, would_claim_uc=True)
+    without_couple_reports = calculate(
+        units, would_claim_uc=False, drop_couple_reports=True
+    )
+    for year in YEARS:
+        for name in [
+            "esa_income",
+            "claimant_or_partner_esa_income",
+            "esa_income_eligible",
+            "is_on_income_related_esa",
+        ]:
+            assert np.allclose(
+                claiming[year][name].astype(float),
+                without_couple_reports[year][name].astype(float),
+                atol=0.01,
+            ), (year, name)
diff --git a/policyengine_uk/tests/test_income_support_eligibility_properties.py b/policyengine_uk/tests/test_income_support_eligibility_properties.py
index 232ec21431..cb3319414a 100644
--- a/policyengine_uk/tests/test_income_support_eligibility_properties.py
+++ b/policyengine_uk/tests/test_income_support_eligibility_properties.py
@@ -308,7 +308,9 @@ def situation(units, capital_as_savings, esa_income, jsa_income):
             people[name] = {k: {YEAR: v} for k, v in inputs.items()}
             people[name]["is_claimant_or_partner"] = {YEAR: claimant_or_partner}
             names.append(name)
-        benunits[f"b{i}"] = {"members": names}
+        # Legacy claimants: a Universal Credit claim would end the couple's
+        # income-related ESA (esa_income_report_closed).
+        benunits[f"b{i}"] = {"members": names, "would_claim_uc": {YEAR: False}}
         households[f"h{i}"] = {"members": names}
         if capital_as_savings:
             households[f"h{i}"]["savings"] = {YEAR: capital}
diff --git a/policyengine_uk/tests/test_income_support_esa_entered_directly.py b/policyengine_uk/tests/test_income_support_esa_entered_directly.py
index ce9b42862f..d3433a7052 100644
--- a/policyengine_uk/tests/test_income_support_esa_entered_directly.py
+++ b/policyengine_uk/tests/test_income_support_esa_entered_directly.py
@@ -44,11 +44,14 @@ def simulation(people, benunit=None):
     return Simulation(
         situation={
             "people": people,
+            # Legacy claimants: a Universal Credit claim would end the
+            # carer's income-related ESA (esa_income_report_closed).
             "benunits": {
                 "b": {
                     "members": names,
                     "income_support_assessable_capital": {YEAR: 0},
                     "esa_income_assessable_capital": {YEAR: 0},
+                    "would_claim_uc": {YEAR: False},
                     **(benunit or {}),
                 }
             },
diff --git a/policyengine_uk/tests/test_income_support_gate_reads_claimant_or_partner_awards.py b/policyengine_uk/tests/test_income_support_gate_reads_claimant_or_partner_awards.py
index b14da3de7b..24894a7fb4 100644
--- a/policyengine_uk/tests/test_income_support_gate_reads_claimant_or_partner_awards.py
+++ b/policyengine_uk/tests/test_income_support_gate_reads_claimant_or_partner_awards.py
@@ -270,11 +270,14 @@ def simulation(families, entered=None):
             name = f"p{i}_{j}"
             people[name] = {k: {YEAR: v} for k, v in inputs.items()}
             names.append(name)
+        # Legacy claimants: a Universal Credit claim would end the couple's
+        # income-related ESA (esa_income_report_closed).
         benunits[f"b{i}"] = {
             "members": names,
             "income_support_assessable_capital": {YEAR: capital},
             "esa_income_assessable_capital": {YEAR: capital},
             "jsa_income_assessable_capital": {YEAR: capital},
+            "would_claim_uc": {YEAR: False},
         }
         for award, values in (entered or {}).items():
             benunits[f"b{i}"][award] = {YEAR: values[i]}
diff --git a/policyengine_uk/tests/test_legacy_award_readers_properties.py b/policyengine_uk/tests/test_legacy_award_readers_properties.py
index 455f4cfe35..a0a5632e9f 100644
--- a/policyengine_uk/tests/test_legacy_award_readers_properties.py
+++ b/policyengine_uk/tests/test_legacy_award_readers_properties.py
@@ -298,10 +298,13 @@ def situation(units, year=YEAR, benunit_inputs=None):
             names.append(name)
         # claims_all_entitled_benefits sums reports across the whole
         # simulation, so fix the take-up mode per benefit unit: the variants
-        # must not share it.
+        # must not share it. The families are on legacy awards and do not
+        # claim Universal Credit, which would end the couple's income-related
+        # ESA (esa_income_report_closed).
         benunits[f"b{i}"] = {
             "members": names,
             "claims_all_entitled_benefits": {year: False},
+            "would_claim_uc": {year: False},
             **{k: {year: v} for k, v in (benunit_inputs or {}).items()},
         }
         households[f"h{i}"] = {
@@ -960,6 +963,7 @@ def test_other_members_esa_never_changes_non_dependant_exemption(drawn):
             benunits[f"nondep_unit_{tag}"] = {
                 "members": unit,
                 "universal_credit": {year: 0},
+                "would_claim_uc": {year: False},
             }
             households[f"h_{tag}"] = {
                 "members": names + unit,
@@ -1023,7 +1027,7 @@ def test_claimant_and_partner_awards_count_in_full_as_their_ctr_income():
     award adds exactly its amount.
     """
     ctr = "council_tax_reduction_applicable_income"
-    no_uc = {"universal_credit": 0}
+    no_uc = {"universal_credit": 0, "would_claim_uc": False}
     claimant_esa = {"claimant": {**CLAIMANT, "esa_income_reported": 5_000}}
     assert np.isclose(
         _difference(ctr, {"claimant": CLAIMANT}, claimant_esa, no_uc), 5_000
@@ -1102,7 +1106,7 @@ def _claimant_and_other(other_report):
     }
     return {
         "people": people,
-        "benunits": {"b": {"members": list(people)}},
+        "benunits": {"b": {"members": list(people), "would_claim_uc": {YEAR: False}}},
         "households": {"h": {"members": list(people)}},
     }
 
@@ -1158,12 +1162,14 @@ def test_late_zero_entry_overrides_the_claimants_reports():
 
 
 def _situation(people, year=YEAR):
+    # Not claiming Universal Credit, which would end the claimant's
+    # income-related ESA (esa_income_report_closed).
     names = list(people)
     return {
         "people": {
             n: {k: {year: v} for k, v in inputs.items()} for n, inputs in people.items()
         },
-        "benunits": {"b": {"members": names}},
+        "benunits": {"b": {"members": names, "would_claim_uc": {year: False}}},
         "households": {"h": {"members": names}},
     }
 
@@ -1289,6 +1295,7 @@ def member(age, role, report, works):
                     "non_dependant_unit": {
                         "members": ["claimant", "other"],
                         "universal_credit": {year: 0},
+                        "would_claim_uc": {year: False},
                     },
                 },
                 "households": {
diff --git a/policyengine_uk/tests/test_legacy_award_work_properties.py b/policyengine_uk/tests/test_legacy_award_work_properties.py
index 1779a07305..3cb5d833d2 100644
--- a/policyengine_uk/tests/test_legacy_award_work_properties.py
+++ b/policyengine_uk/tests/test_legacy_award_work_properties.py
@@ -151,10 +151,13 @@ def situation(units, year):
             people[name]["is_claimant_or_partner"] = {year: claimant_or_partner}
             people[name]["is_parent"] = {year: claimant_or_partner and bool(children)}
             names.append(name)
+        # Legacy claimants: a Universal Credit claim would end the couple's
+        # income-related ESA (esa_income_report_closed).
         benunits[f"b{i}"] = {
             "members": names,
             "esa_income_assessable_capital": {year: capital},
             "jsa_income_assessable_capital": {year: capital},
+            "would_claim_uc": {year: False},
         }
         households[f"h{i}"] = {"members": names}
     return {"people": people, "benunits": benunits, "households": households}
diff --git a/policyengine_uk/tests/test_legacy_closure_scope.py b/policyengine_uk/tests/test_legacy_closure_scope.py
index 4126a21ddc..e3f4428e40 100644
--- a/policyengine_uk/tests/test_legacy_closure_scope.py
+++ b/policyengine_uk/tests/test_legacy_closure_scope.py
@@ -36,11 +36,15 @@ def household(year, claimant=None, partner=None, outside=None, child=False):
             name: {key: {str(year): value} for key, value in inputs.items()}
             for name, inputs in members.items()
         },
+        # The family does not claim Universal Credit of its own accord: that
+        # claim would end the couple's income-related ESA
+        # (esa_income_report_closed).
         "benunits": {
             "unit": {
                 "members": list(members),
                 "esa_income_assessable_capital": {str(year): 0},
                 "jsa_income_assessable_capital": {str(year): 0},
+                "would_claim_uc": {str(year): False},
             }
         },
         "households": {"household": {"members": list(members)}},
diff --git a/policyengine_uk/tests/test_winter_heating_payment_properties.py b/policyengine_uk/tests/test_winter_heating_payment_properties.py
index 2639d8881b..66b165de44 100644
--- a/policyengine_uk/tests/test_winter_heating_payment_properties.py
+++ b/policyengine_uk/tests/test_winter_heating_payment_properties.py
@@ -208,6 +208,10 @@ def situation(drawn, year):
                     variable: {year: AWARD if unit["award"] == key else 0}
                     for key, variable in AWARD_INPUTS.items()
                 },
+                # The family claims Universal Credit only when it is on it: a
+                # claim would end the couple's income-related ESA
+                # (esa_income_report_closed).
+                "would_claim_uc": {year: unit["award"] == "UC"},
             }
             benunits[f"h{h}_b{u}"] = benunit
         hh[f"h{h}"] = {"members": names, "country": {year: household["country"]}}
diff --git a/policyengine_uk/utils/benefit_unit.py b/policyengine_uk/utils/benefit_unit.py
index 2df7693ab5..330a9ade55 100644
--- a/policyengine_uk/utils/benefit_unit.py
+++ b/policyengine_uk/utils/benefit_unit.py
@@ -6,6 +6,15 @@
 # each other are the same, and an award within half a penny of zero is none.
 HALF_PENNY = 0.005
 
+# For each award award_of_members reads, the person-level variable saying the
+# award on a member's report has ended. Its formula leaves those reports out:
+# income-related ESA also ends for the claimant and partner of a family that
+# claims Universal Credit (esa_income_report_closed).
+REPORT_CLOSED = {
+    "esa_income": "esa_income_report_closed",
+    "jsa_income": "person_legacy_benefits_closed",
+}
+
 
 def add_for_members(benunit, period, variables, members):
     """Sum variables over the benefit-unit members a means test counts.
@@ -82,7 +91,7 @@ def award_of_members(benunit, period, award, report, award_on_reports, members):
     members_reported = benunit.sum(reported * members)
     # Formula awards omit reports whose own award has closed. Keep the raw
     # totals above for disable_simulated_benefits and direct-value provenance.
-    open_reported = reported * ~person("person_legacy_benefits_closed", period)
+    open_reported = reported * ~person(REPORT_CLOSED[award], period)
     award_on_all_reports = award_on_reports(benunit, period, benunit.sum(open_reported))
     award_on_members_reports = award_on_reports(
         benunit, period, benunit.sum(open_reported * members)
diff --git a/policyengine_uk/variables/gov/dwp/esa_income.py b/policyengine_uk/variables/gov/dwp/esa_income.py
index 7b723bf4c6..e382b53e47 100644
--- a/policyengine_uk/variables/gov/dwp/esa_income.py
+++ b/policyengine_uk/variables/gov/dwp/esa_income.py
@@ -16,7 +16,10 @@ class esa_income(Variable):
     label = "ESA (income-based)"
     documentation = (
         "Reported income-related ESA screened through bounded capital and "
-        "remunerative work tests (esa_income_eligible). "
+        "remunerative work tests (esa_income_eligible). Reports whose award "
+        "has ended are left out (esa_income_report_closed): the owner's "
+        "legacy benefits have closed, or the owner is the claimant or "
+        "partner of a family that claims Universal Credit. "
         "This is not a full entitlement model."
     )
     definition_period = YEAR
@@ -26,6 +29,6 @@ def formula(benunit, period, parameters):
         person = benunit.members
         reported_award = benunit.sum(
             person("esa_income_reported", period)
-            * ~person("person_legacy_benefits_closed", period)
+            * ~person("esa_income_report_closed", period)
         )
         return income_related_esa_award(benunit, period, reported_award)
diff --git a/policyengine_uk/variables/gov/dwp/esa_income_eligible.py b/policyengine_uk/variables/gov/dwp/esa_income_eligible.py
index c071f77373..690416d60e 100644
--- a/policyengine_uk/variables/gov/dwp/esa_income_eligible.py
+++ b/policyengine_uk/variables/gov/dwp/esa_income_eligible.py
@@ -26,9 +26,10 @@ class esa_income_eligible(Variable):
         "in it, so when the claimant or partner reports, another member's "
         "report is paid or not with their claim. Whether that member is on "
         "the award themselves (is_on_income_related_esa) is tested on their "
-        "own claim. Reports whose owner has closed legacy benefits are left "
-        "out before choosing candidates (person_legacy_benefits_closed). "
-        "This is not a full "
+        "own claim. Reports whose award has ended are left out before "
+        "choosing candidates (esa_income_report_closed): the owner's legacy "
+        "benefits have closed, or the owner is the claimant or partner of a "
+        "family that claims Universal Credit. This is not a full "
         "entitlement model."
     )
     definition_period = YEAR
@@ -45,7 +46,7 @@ def formula(benunit, period, parameters):
         person = benunit.members
         capital = benunit("esa_income_assessable_capital", period)
         reports_award = (person("esa_income_reported", period) > 0) & ~person(
-            "person_legacy_benefits_closed", period
+            "esa_income_report_closed", period
         )
         claimant_or_partner = person("is_claimant_or_partner", period)
         # The candidate claimants: the claimant or partner who reports the
diff --git a/policyengine_uk/variables/gov/dwp/esa_income_report_closed.py b/policyengine_uk/variables/gov/dwp/esa_income_report_closed.py
new file mode 100644
index 0000000000..dd087317c8
--- /dev/null
+++ b/policyengine_uk/variables/gov/dwp/esa_income_report_closed.py
@@ -0,0 +1,48 @@
+from policyengine_uk.model_api import *
+
+
+class esa_income_report_closed(Variable):
+    value_type = bool
+    entity = Person
+    label = "Income-related ESA award on this person's report has ended"
+    documentation = (
+        "Whether the income-related ESA award on this person's report has "
+        "ended, so the model leaves the report out of esa_income, "
+        "esa_income_eligible and the claimant's or partner's award "
+        "(claimant_or_partner_esa_income). It ends when the person's legacy "
+        "benefits close (person_legacy_benefits_closed), or when the person "
+        "is the claimant or partner of a family that claims Universal Credit "
+        "(claims_universal_credit). A claim for Universal Credit brings the "
+        "abolition of income-related ESA (Welfare Reform Act 2012 s.33(1)(b)) "
+        "into force for the claimant's old style ESA award from the first day "
+        "of the period claimed for, whether or not Universal Credit is "
+        "awarded (SI 2013/983 art. 4(1), (2)(a), (3)(a) and (9), and the later "
+        "commencement orders that extended it to further postcode districts; "
+        "in Northern Ireland, Welfare Reform (Northern Ireland) Order 2015 "
+        "art. 39(1)(b) and SR 2017/190 art. 6(1) to (3) and (6)). For claims "
+        "from 22 July 2020 the award runs on for two weeks after that day (SI "
+        "2019/1152 reg. 5), which this annual model does not represent. A "
+        "contributory allowance in the award continues as new style ESA "
+        "(esa_contrib). A member who is neither the claimant nor the partner, "
+        "such as a non-dependent adult, claims in their own right and is not "
+        "part of the family's Universal Credit claim, so the claim does not "
+        "end their award. The model applies this in every year and area: the "
+        "postcode districts named in the commencement orders are not "
+        "modelled."
+    )
+    definition_period = YEAR
+    reference = (
+        "https://www.legislation.gov.uk/ukpga/2012/5/section/33",
+        "https://www.legislation.gov.uk/uksi/2013/983/article/4",
+        "https://www.legislation.gov.uk/uksi/2019/1152/regulation/5",
+        "https://www.legislation.gov.uk/uksi/2025/1148/article/3A",
+        "https://www.legislation.gov.uk/nisi/2015/2006/article/39",
+        "https://www.legislation.gov.uk/nisr/2017/190/article/6",
+        "https://www.legislation.gov.uk/nisr/2025/176/article/3A",
+    )
+
+    def formula(person, period, parameters):
+        claims_uc = person.benunit("claims_universal_credit", period)
+        return person("person_legacy_benefits_closed", period) | (
+            person("is_claimant_or_partner", period) & claims_uc
+        )
diff --git a/policyengine_uk/variables/gov/dwp/universal_credit/claims_universal_credit.py b/policyengine_uk/variables/gov/dwp/universal_credit/claims_universal_credit.py
index 21a1bdc84f..952acc87e0 100644
--- a/policyengine_uk/variables/gov/dwp/universal_credit/claims_universal_credit.py
+++ b/policyengine_uk/variables/gov/dwp/universal_credit/claims_universal_credit.py
@@ -10,17 +10,19 @@ class claims_universal_credit(Variable):
         "anyway (would_claim_uc), or it claims when DWP moves it off its "
         "legacy benefits (claims_uc_at_legacy_closure). Universal Credit is "
         "paid only to claiming families. A claim ends the family's Housing "
-        "Benefit continuing award and Child Tax Credit. Once DWP moves a "
-        "family off legacy benefits (legacy_benefits_closed) all its legacy "
-        "awards end; for other claimants the overlap of Universal Credit "
-        "with Working Tax Credit, Income Support, income-related ESA and "
-        "income-based JSA is not modelled, nor is Housing Benefit for "
-        "specified or temporary accommodation."
+        "Benefit continuing award and Child Tax Credit, and the claimant's "
+        "and partner's income-related ESA (esa_income_report_closed). Once "
+        "DWP moves a family off legacy benefits (legacy_benefits_closed) all "
+        "its legacy awards end; for other claimants the overlap of Universal "
+        "Credit with Working Tax Credit, Income Support and income-based JSA "
+        "is not modelled, nor is Housing Benefit for specified or temporary "
+        "accommodation."
     )
     definition_period = YEAR
     reference = (
         "https://www.legislation.gov.uk/uksi/2014/1230/regulation/8",
         "https://www.legislation.gov.uk/uksi/2014/1230/regulation/46",
+        "https://www.legislation.gov.uk/uksi/2013/983/article/4",
     )
 
     def formula(benunit, period, parameters):