Count Carer Support Payment as Council Tax Reduction income

[MaxGhenis]

Fixes #1955

#1952 and #1994 have merged. On main, carer_support_payment is the Carer Support Payment component only, after the CSP Regs reg 16(2) overlapping-benefit reduction. carer_support_payment_pre_overlap is the same component before that reduction, and the Scottish Carer Supplement is a separate variable, scottish_carer_supplement.

What changes

• The fix. council_tax_reduction_applicable_income listed carers_allowance but not the Carer Support Payment. From 2025 the model moves Scottish carers from Carer's Allowance (CA) to Carer Support Payment (CSP), so their CTR income left out their carer's benefit. This PR adds carer_support_payment_pre_overlap to the list. scottish_carer_supplement stays off it.
• Which CSP amount. The pre-reduction amount is provisional. Whether Scottish CTR counts CSP before or after reg 16(2) is an open question, set out below and queued for a ruling. Until then, CTR counts the amount before the reduction, which is what the model counted before Reduce Carer's Allowance and Carer Support Payment by overlapping benefits #1994 modelled the reduction. A ruling the other way swaps this list entry for carer_support_payment and updates the two tripwire cases.
• Citations. The variable's reference now also lists SSI 2021/249 reg 57 and SSI 2012/319 reg 27. scottish_carer_supplement's documentation now says that Scottish CTR does not count it either.
• Changelog. changelog.d/1955.fixed.md.

Law

Re-read on 2026-10-02 from fresh legislation.gov.uk CLML fetches (valid from 2026-04-01). The text is unchanged from the 2026-09-30 copies. No instrument made or in force since 2026-04-01 touches carer income in either Scottish scheme. SSI 2026/259 (in force 6.11.2026) amends both instruments elsewhere, and its only change to the reg 57(1) list omits head (v), widowed mother's allowance.

• Working age. Council Tax Reduction (Scotland) Regulations 2021 (SSI 2021/249) reg 57(1) is a closed list: "An applicant's unearned income is any of their income ... falling within the following descriptions".
  • Head (b) covers "any of the following benefits to which the applicant is entitled, subject to any adjustment to the amount payable in accordance with Regulations under section 73 of the Social Security Administration Act 1992". It includes (iva) "carer support payment", inserted on 19.11.2023 by SSI 2023/258 reg 8(3).
  • Reg 4(1) has defined CSP as "the Carer Support Payment component of Carer Support" since 15.3.2026 (SSI 2025/340 Sch 1 para 10(2)).
  • The Scottish Carer Supplement appears nowhere in the instrument except Sch 4 para 24(e), a 52-week capital disregard.
  • Reg 57(1)(o) catches only ITTOIA 2005 Part 5 income. The supplement is taxed under ITEPA 2003 Part 10 (s.660 Table A, inserted by SI 2026/93), so (o) does not catch it.
• Pension age. Council Tax Reduction (State Pension Credit) (Scotland) Regulations 2012 (SSI 2012/319) reg 27(1)(j) counts "social security benefits other than" a list. CSP is not on the list.
  • (xxi) excepts the Carer's Allowance Supplement.
  • (xxia) excepts the Carer Additional Person Payment and (xxib) "the Scottish Carer Supplement component of Carer Support". SSI 2025/340 Sch 1 para 8(3) inserted both from 15.3.2026.
  • Reg 2(1) defines CSP as the component.
• No disregard of CSP above the CA amount. Searches of both whole instruments for "in excess of" and "carer support payment" find no disregard of CSP. The GB schemes have one: SI 2012/2885 Sch 5 para 26 (England pensioners), SPC Regs Sch IV para 19, HB (SPC) Sch 5 para 25, HB Sch 5 para 74, and the UC reg 66(1)(b)(iiia) cap. So CSP counts in full. A cap would not bind in any case, because CSP and CA are both £83.30 in 2025-26 and both £86.45 in 2026-27.
• Tax.
  • At working age, SSI 2021/249 deducts tax and NI from earnings only (reg 50(3)(a); regs 49(6)(b) and 51(2)). Unearned income counts gross.
  • At pension age, SSI 2012/319 reg 31(12) reads: "In the case of any income taken into account for the purpose of calculating a person's income, any amount payable by way of tax must be disregarded." NI comes off earnings only.
  • In law, then, the supplement does not reach Scottish CTR income, and neither does the tax on it.
  • The model deducts the claimant's and partner's whole income tax and NI from CTR income, for every scheme. That predates this PR. So in the model the taxable supplement reaches CTR income through the tax charged on it, and in no other way. Income Support and tax credits also count it, through social_security_income, but the model pays neither from 2026, when the supplement starts (income_support.active is false from 2026-04-01 and tax_credits.active from 2025-04-06). Council Tax Reduction income deducts the family's whole income tax, not the tax the schemes allow #2090 records the approximation: it over-deducts at working age and deducts tax on income that is not counted at pension age.
• England and Wales. The model pays CSP only in Scotland (carer_support_payment requires country == SCOTLAND), so the shared list cannot change CTR there. For the record:
  • SI 2012/2885 counts CSP for English pensioners (Sch 1 para 16(1)(j)), after the CSP Regs reg 16(2) reduction (para 16(4)(g)), and disregards any excess over CA (Sch 5 para 26). Its reg 2(1) still defines CSP as "carer's assistance given in accordance with" the CSP Regs, not just the component, so on its face it takes in the supplement, which the excess disregard then removes.
  • SI 2012/2886 and the Welsh schemes (WSI 2013/3029, 2013/3035) do not mention CSP or the supplement.

Rates (weekly): CSP £86.45 and the supplement £11.70 from 5.4.2026 (SSI 2023/302 reg 16(1) and (1A), as amended by SSI 2026/170 reg 12(3)). CSP was £83.30 in 2025-26. The supplement was £11.29 from 15.3.2026 to 4.4.2026 (SSI 2025/340 reg 3(12)(c)).

Open question for #1994: does CTR count CSP before or after its overlapping-benefit reduction?

Since #1994, main applies CSP Regs (SSI 2023/302) reg 16(2), under which "the amount of Carer Support Payment that is to be given ... is to be reduced" by State Pension, contributory ESA and similar benefits. Two independent readings of fresh texts reach the same answer at each age, with the confidence shown:

• Pension age on the general-rules route (SSI 2012/319 regs 26 and 27). The text points to the amount before the reduction, at least where some CSP is paid (low-to-moderate confidence; where reg 16(2)(b) cuts CSP to £0 there is arguably no payment to gross up).
  • Reg 27(3) counts a benefit at "the amount before the deduction is made" for any deduction "other than an adjustment specified in paragraph (5)".
  • Reg 27(5) lists the Overlapping Benefits Regulations 1979, the Hospital In-Patients Regulations 2005, SSCBA s.30DD/30E and WRA 2007 s.3. It does not list CSP Regs reg 16(2).
  • Every GB scheme with the same gross-up rule was amended to list reg 16(2): SPC Regs reg 15(4)(g) and HB (SPC) reg 29(4)(g) (SI 2023/1218), and SI 2012/2885 Sch 1 para 16(4)(g) (SI 2025/39). In the carer premium rules, SSI 2023/258 inserted Sch 1 para 6(1)(ab) citing "regulation 16" and SSI 2025/340 changed that to 16(2), but neither added reg 16(2) to reg 27(5).
  • Against: reg 16(2) fixes what CSP "is to be given" (SS(S)A 2018 s.28(2)(b)), and the CSP Regs themselves keep it apart from "giving Carer Support Payment by way of deduction" (reg 16(5), reg 26). Counting £86.45 a week that is never paid double counts the State Pension that extinguished it. Sch 1 para 6(1)(ab) also has to deem such a carer to be in receipt of CSP for the premiums, which implies that without the deeming they are not.
  • Applicants on Guarantee Credit are unaffected (reg 24). Savings-Credit-only cases use the Secretary of State's assessment (reg 25), which counts CSP after reg 16(2) (SPC reg 15(4)(g)).
• Working age (SSI 2021/249 reg 57(1)(b)). The text points to the amount after the reduction (moderate confidence on one reading, moderate-to-high on the other).
  • Head (b) counts benefits "to which the applicant is entitled, subject to any adjustment ... in accordance with Regulations under section 73 of the Social Security Administration Act 1992".
  • Reg 16(2) is made under the Social Security (Scotland) Act 2018 (SSI 2023/302's enabling powers), not s.73. SSI 2021/249 has no general gross-up rule like reg 27(3).
  • The 2018 Act frames entitlement as entitlement to "be given" what the regulations prescribe, so the amount the applicant is entitled to is the reduced one.
  • Against: the express s.73 proviso implies that "entitled" otherwise means the amount before adjustments, and Sch 1 paras 5(4)(c) and 6(1)(b) treat a person whose CSP is cut by reg 16 as one who "would be in receipt" of it.

This PR counts the amount before the reduction at both ages for now, which keeps CTR where it was before #1994. That matches the pension-age reading but not the working-age one. The choice is queued for a ruling and may flip either age.

Two YAML cases are tripwires for the choice. In each, the carer's overlapping benefit exceeds the CSP rate, so carer_support_payment is 0 and carer_support_payment_pre_overlap is 86.45 × 52: State Pension at pension age, contributory ESA at working age. Each fails if CTR income drops the CSP, so a ruling has to be applied deliberately.

How PolicyEngine models Scottish CTR

simulated_council_tax_reduction_benunit runs one national scheme for Scotland, at working age and pension age alike. It has:

• a maximum support rate of 1 and a £16,000 capital limit;
• withdrawal at 20% of income above the applicable amount (gov.local_authorities.scotland.council_tax_reduction);
• the HB applicable amounts and premiums, including the carer premium;
• this shared income variable, with the pension-age Guarantee Credit and Savings Credit routes (SSI 2012/319 regs 24 and 25).

The national scheme counts UC as income. Draft #1966 moves Scottish and Welsh working-age claims onto their own income and UC rules, and after it this change still governs Scottish pension-age CTR.

#1966 has a problem now that #1952 is on main. Its council_tax_reduction_working_age_unearned_income lists carer_support_payment but then subtracts supplement / (rate + supplement) of it, on the old assumption that carer_support_payment includes the supplement. On current main that removes £535.88 a year (4,495.40 × 11.70 / 98.15) of genuine CSP in 2026, so #1966 must drop the subtraction. A note to that effect is on #1966.

Household examples (2026 unless stated; council tax £2,000; YAML cases)

Case	CTR income, main → this PR	CTR, main → this PR
Single carer aged 40, Scotland, private pension £7,000, no UC	7,000 → 11,495.40 (+86.45 × 52)	2,000 → 1,195.40 = 2,000 − 0.2 × (11,495.40 − 7,472.40)
Same, qualifying by a reported award	7,000 → 11,495.40	2,000 → 1,195.40
Same carer in Wales, on CA (control)	11,495.40 → 11,495.40	1,195.40 → 1,195.40
Scottish carer who does not claim (control; no claim means no carer premium, SSI 2021/249 Sch 1 paras 5(2), 6(1))	7,000 → 7,000	1,593.72 → 1,593.72
Carer aged 40 on contributory ESA £5,000 (above the CSP rate, so none is paid), Scotland	5,000 → 9,495.40	2,000 → 1,595.40
The first carer in 2025 (CSP £83.30, no supplement)	7,000 → 11,331.60	2,000 → 1,173.25
The first carer in 2024 (still on CA £81.90, control)	11,258.80 → 11,258.80	1,163.68 → 1,163.68. On main the award jumps to 2,000 when CA becomes CSP in 2025; with this PR it does not.
Pensioner carer aged 70, Scotland, private pension £14,000	12,732.91 → 17,228.31. The supplement adds only its £121.68 of tax.	2,000 → 1,717.50
Pensioner couple, partner a carer, Scotland, pensions £12,000 + £6,500	18,500 → 22,995.40	2,000 → 1,888.52
Unmarried pensioner couple, partner a carer, State Pensions £15,000 + £7,400 (the partner's is above the CSP rate, so none is paid)	21,938.30 → 26,433.70	2,000 → 1,200.86
Pensioner couple on Guarantee Credit (control: reg 24 disregards all income)	0 → 0	2,000 → 2,000
English pensioner carer on CA (control)	17,310.32 → 17,310.32	1,701.10 → 1,701.10

Every row is a YAML case. The "before" CTR income comes from running the same file on main 325d585. The runner reports only the first mismatch in each case, so for the failing rows the "before" award is derived: each main income is below its applicable amount, so the award is the full 2,000. All 12 cases pass on this head.

Tests

• YAML. council_tax_reduction_carer_support_payment.yaml has 12 cases, each worked from the rates with the arithmetic in comments. The 2026 rates are statutory. The 2025 case uses the model's 2025-26 carer premium and personal allowance (46.38 and 92.04), which are 2p and 1p below the statutory amounts (2025-26 legacy carer premium and HB personal allowance are extrapolated, not statutory #2110).
  • On this head all 12 pass.
  • On main 325d585, 7 fail, every one on council_tax_reduction_applicable_income, short by exactly the CSP (for example "7000 differs from 11495.40"). The 5 controls pass on both: Wales on CA, a Scottish carer who does not claim, 2024 on CA, the Guarantee Credit couple and the English pensioner.
  • The two tripwire cases are described under the open question above.
• Properties. test_council_tax_reduction_carer_income_properties.py holds 4 Hypothesis properties.
  • Each draw is a family in Scotland in 2026, single or couple, either working-age without UC or pension-age, with the carer qualifying by caring hours or by a reported award. Each family runs on a private-pension grid from £0 to £40,000, with and without the claim. One explicit example is pinned: a Scottish carer aged 80 with no State Pension, who moves between the general rules and Savings Credit only across the grid.
  1. Counts the component. Where both runs follow the general rules (neither SSI 2012/319 reg 24 nor reg 25 applies), claiming CSP raises CTR income, before tax and NI and apart from the other counted benefits, by exactly 86.45 × 52, before any overlapping-benefit reduction. The award never rises. Where both awards are partial, it falls by 20% of the rise in income less the rise in the applicable amount (the carer premium comes with the claim). The supplement is paid in full wherever some CSP is paid, and not otherwise.
  2. Invariant to the supplement except through income tax. Setting gov.social_security_scotland.carer_support_payment.supplement to 0 leaves CSP and the other benefits CTR counts (Child Benefit, the income-related benefits, UC and tax credits) unchanged. On the general rules it also leaves CTR income plus income tax unchanged. The supplement never lowers the award, on any route. Where both awards are partial on the general rules, it raises the award by exactly 20% of the tax on the supplement.
  3. Differential against Housing Benefit. On the general rules, and where Guarantee Credit does not passport HB, HB applicable income before its disregard, childcare element and tariff income equals CTR income less the part of CSP an overlapping benefit removes. HB counts CSP after the reduction (HB (SPC) reg 29(4)(g)). This holds in England, Wales and Scotland.
  4. Pension Credit routes. With Guarantee Credit, CTR income is nil. With Savings Credit only, it equals Pension Credit income plus the Pension Credit paid.
  • Each general-rules compared mask in properties 1-3 is asserted to cover at least one cell; at the top of the pension grid every family follows the general rules with positive income. The 20% checks run where both awards are partial, which the pinned example reaches at a £20,000 pension.
  • On this head, all 4 pass.
  • On main 325d585, properties 1 and 3 fail and 2 and 4 pass:
    • Property 1's counterexample is the pinned carer aged 80. Their CTR income rises by 0 instead of 4,495.40.
    • Property 3 fails because HB counts CSP and main's CTR does not.
    • Property 2 also failed on main before Reduce Carer's Allowance and Carer Support Payment by overlapping benefits #1994 (84f5ad4): a Scottish carer aged 92 with State Pension £5,902 and private pension £8,000 was moved onto the Savings-Credit-only route by the supplement's tax, and the award fell from 500 to 228.02. Since Reduce Carer's Allowance and Carer Support Payment by overlapping benefits #1994 that State Pension removes the carer's CSP and supplement, and Guarantee Credit applies, so that example no longer fails on main.
• Mutation check. On this head with scottish_carer_supplement also added to the list, 4 YAML cases fail, each by exactly 608.40 (11.70 × 52): the two working-age CSP cases, the single pensioner and the pensioner couple. The two tripwire cases pay no supplement, so they do not move. Properties 1, 2 and 3 fail.
• Neighbouring suites on this head. YAML under gov/local_authorities, gov/dwp, gov/social_security_scotland and finance: 1,128 passed. Pytest for test_carer_support_payment.py, test_council_tax_reduction_pension_credit_properties.py, test_housing_benefit_pension_age_properties.py and test_pension_credit_carer_income_properties.py: 20 passed. The full suite runs in CI.

Invariants (they hold for every input in the drawn domain):

• a conservation identity (property 1);
• a metamorphic relation over the supplement (property 2);
• a differential identity with HB (property 3);
• the Pension Credit route identities (property 4);
• monotonicity of the award in the carer's benefit and the supplement (properties 1 and 2).

They compare the model's own measures, so they hold whatever carer's benefit the model pays.

Enhanced FRS impact

Real microsimulation runs, two in total: main a494425 and this head (0f5a5b4), each over 2025-2030, on the published Enhanced FRS 2024-25: a local copy of enhanced_frs_2024_25.h5 from Hugging Face policyengine-uk-data-private, uploaded for version 1.57.4. Its sha256, 03fe15e4…, matches the LFS object on Hugging Face main, checked on 2026-10-03. Totals are summed in float64.

Year	CTR total on main	Change in CTR
2025	£2,286.0m	−£0.36m
2026	£2,359.1m	−£0.37m
2027	£2,424.2m	−£0.39m
2028	£2,494.4m	−£0.41m
2029	£2,558.6m	−£0.43m
2030	£2,616.7m	−£0.45m

In 2026:

• CTR income rises by £508m, all of it in Scotland: £297m at working age and £211m at pension age. Where the zero floor does not bind, each benefit unit's rise equals its CSP to within £0.003. Units without CSP change by exactly £0.
• The award falls only for Scottish working-age benefit units; no pension-age award changes. The total rests on a small number of survey records, so it is imprecise, and record-level detail is not reported.
• The dataset effect is small because few CSP families would claim CTR in the data, and most of those who would already received no CTR on main.
• Unchanged: HB, UC, Pension Credit, poverty (BHC and AHC), and every English, Welsh and Northern Irish figure. Household net income and HBAI net income fall by exactly the CTR change.

Earlier comparisons against older mains gave −£0.38m in 2026 against b4d613a8, kept with the 2026-10-01 evidence, and −£0.98m against 84f5ad4 to 9eccc54. The rise in CTR income is £508m in every run, so the award change moves with main's baseline, not with this PR's change. The scripts (dataset_impact.py, compare_impact.py) and outputs are kept outside the repo.

History

The branch has merged main several times. Its diff against main a494425 is the files listed under What changes plus the tests. One upstream merge in its history, 3729880 (#1943's merge of main), resolved a conflict in gov/dwp/universal_credit/means_test/income_definitions/unearned.yaml by keeping both citation sets and State Pension. That merge is already on main and is not part of this PR's diff.

Axiom

axiom: TheAxiomFoundation/rulespec-uk#432 queued. No rulespec-uk module decides Scottish CTR income, and none of SSI 2021/249 reg 57 or reg 4, or SSI 2012/319 reg 27 or reg 2, is in the pinned corpus release. The issue sets out the corpus ingest, a pasteable review_finding for each regulation, and companion tests from the same statutory rates as the YAML cases. It encodes the open reg 16(2) treatment as two outputs, one before and one after the reduction, so the ruling picks between them.

Interactions with other open PRs

• Reduce Carer's Allowance and Carer Support Payment by overlapping benefits #1994 (CA and CSP overlapping-benefit reduction), merged. It made carer_support_payment the amount after reg 16(2), added carer_support_payment_pre_overlap, and tied the carer premium to entitlement. This PR reads carer_support_payment_pre_overlap until the open question is ruled on. The two tripwire cases check both amounts.
• Give Scotland and Wales working-age council tax reduction their own rules (UC routes, passport, child amounts) #1966. Drop the supplement-share subtraction (see above).
• Count contributory ESA, Maternity Allowance, industrial injuries benefit and capped Carer Support Payment as UC unearned income #1958 (UC reg 66), merged. No overlap.

Follow-ups filed

• Council Tax Reduction income deducts the family's whole income tax, not the tax the schemes allow #2090: CTR income deducts the family's whole income tax.
• 2025-26 legacy carer premium and HB personal allowance are extrapolated, not statutory #2110: the 2025-26 legacy carer premium and HB personal allowance are extrapolated (46.38 and 92.04), not the statutory 46.40 and 92.05. With the statutory amounts this PR's 2025 case would give 1,173.56 rather than 1,173.25.
• Pension-age CTR counts child benefit, SSP and SMP that SSI 2012/319 reg 27(1)(j) excepts #2111: pension-age CTR counts child benefit, SSP and SMP, which SSI 2012/319 reg 27(1)(j) excepts.

🤖 Generated with Claude Code

[MaxGhenis]

One line for this PR to update now that #2049 has merged.

The module docstring of policyengine_uk/tests/test_pension_credit_carer_income_properties.py (lines 6-7) says Council Tax Reduction "counted Carer's Allowance (it does not yet count Carer Support Payment: #1955)". Once this PR makes CTR count Carer Support Payment, that clause is stale. Please change it to say Council Tax Reduction counts both. No test logic depends on it.

🤖 Generated with Claude Code

[MaxGhenis]

Merged under d780 ("merge on gates"), at reviewed head 0f5a5b4 with a merge commit (20590dc).

Gates:

• gh pr checks was all green on 0f5a5b4. The Test job took 36m34s.
• The PR was MERGEABLE.
• Independent reviews (GPT-6.1 Sol, hard tier), each of which approved:
  • c188ae9: review_c188ae9_out.md.
  • 0f5a5b4, a delta review over a main-only merge: review_0f5a5b4_out.md.
  • Earlier rounds had asked for changes, and every finding was addressed.

State after merge:

• The provisional reading stays until it is ruled on: CTR counts carer_support_payment_pre_overlap. The two tripwire YAML cases guard it.
• Axiom: Encode SSI 2021/249 reg 57(1)(b)(iv)-(iva) and SSI 2012/319 reg 27(1)(j), (3), (5): Carer Support Payment counts as Scottish CTR income and the Scottish Carer Supplement does not TheAxiomFoundation/rulespec-uk#432 is queued.
• Follow-ups: Council Tax Reduction income deducts the family's whole income tax, not the tax the schemes allow #2090, 2025-26 legacy carer premium and HB personal allowance are extrapolated, not statutory #2110 and Pension-age CTR counts child benefit, SSP and SMP that SSI 2012/319 reg 27(1)(j) excepts #2111.

🤖 Generated with Claude Code