Give Scotland and Wales working-age council tax reduction their own rules (UC routes, passport, child amounts)

[MaxGhenis]

Fixes #1962. Also closes #1935 for Scotland and Wales.

axiom: SSI 2021/249 regs 13(11), 35, 42, 49(6), 50(3), 57(1)(p), Sch 1 para 6(1), Sch 3 para 4(3); WSI 2013/3029 Sch 6 paras 3, 9, 15(3), Sch 7 paras 1-4 and 14, Sch 9 para 4, Sch 9 and 10 para 8 | TheAxiomFoundation/rulespec-uk#393 queued (extended for the review fixes in this comment)

What was wrong

Working-age households in Scotland and Wales ran through the pension-age means test, built on Housing Benefit parameters. On main (41a996e) in 2026, simulated working-age CTR was:

• Scotland: £0.045bn (0.056m households), against £0.134bn (0.343m) reported in the FRS;
• Wales: £0.000bn (0.001m), against £0.072bn (0.111m) reported.

Four legal defects caused it:

1. Universal Credit. The whole UC award, including the housing costs element, counted as income against a Housing Benefit personal allowance with no children in it. The law is different in each country:
   • Wales (WSI 2013/3029 Sch 6 paras 3 and 9) compares the Secretary of State's UC income plus the award with the UC maximum amount. The housing and child elements cancel, and a UC claimant with no earnings gets the maximum reduction.
   • Scotland (SSI 2021/249 regs 35, 42, 57(1)(p) and (2)(d)) keeps its own applicable amount. It counts as income only the UC child element (with disabled-child additions) plus the childcare costs element, capped at the award. Earnings are measured on the UC basis with the CTR earnings disregards and no work allowance.
2. No passport. Claimants on Income Support, income-based JSA or income-related ESA were means-tested. The law gives them the maximum reduction: SSI 2021/249 reg 13(11); WSI 2013/3029 Sch 9 para 8 and Sch 10 para 8.
3. Applicable amounts.
   • There were no child amounts: Scotland's child premium is £109.85 per child (25% above Housing Benefit since 2017), Wales's child amount £87.88.
   • There was no family premium: £20.22 in Wales, and in Scotland until it closed to new claims on 1 May 2016.
   • There was no disabled child premium or child enhanced disability premium.
   • Welsh personal allowances were Housing Benefit's (£95.55 / £75.65 / £150.15) instead of Wales's own (£101.85 / £80.60 / £159.85).
   • The adult premiums were the projected DWP amounts, not the devolved ones, which differ in most years (2025-26 disability premium: £47.48 projected against £43.20 in law).
   • The carer premium was paid once for a couple even when both qualify.
4. Income.
   • Child Benefit was counted; both countries disregard it.
   • There were no earnings disregards (£5, £10, £20 or £25, plus £17.10), no childcare deduction and no tariff income from capital.
   • Actual interest, dividends and rent were counted, where the law treats them as capital.

What this changes

simulated_council_tax_reduction_benunit sends a claim down a new working-age route when the household is in Scotland or Wales and council_tax_reduction_claim_pensioner (the per-claim scheme flag the national formula routes on, from #1944 and #2006) is false. Every person mask in the route goes through working_age/_applicant.py, so #2078's applicant identity is a one-line swap. The new variables are in council_tax_reduction/working_age/:

Variable	Rule
council_tax_reduction_devolved_working_age	Scotland or Wales, not a CTR pensioner. Mixed-age UC couples take this route (WSI 2013/3029 reg 3; SSI 2021/249 reg 3).
council_tax_reduction_working_age_applicable_amount	Wales with UC: uc_maximum_amount. Otherwise: personal allowance, child amounts, and the devolved adult premiums (council_tax_reduction_working_age_adult_premiums).
council_tax_reduction_working_age_personal_allowance	Couple / lone parent / single 25+ / single under 25. The higher single rate also applies on main-phase ESA and, in Scotland, on UC with LCW.
council_tax_reduction_working_age_child_amounts	Per-child amount, family premium, disabled child premium, child enhanced disability premium.
council_tax_reduction_working_age_adult_premiums, _carers	Disability, severe disability, enhanced disability premiums at the devolved amounts (who qualifies follows the legacy premium variables), and a carer premium for each claimant or partner entitled to Carer's Allowance or Carer Support Payment, including an entitlement an overlapping benefit reduces to nil (WSI 2013/3029 Sch 7 para 14(1); SSI 2021/249 Sch 1 para 6(1)(a)-(b)). Scotland also counts an award of UC that includes the carer element (para 6(1)(c)), as one carer when no one in the family is entitled to a carer benefit.
council_tax_reduction_working_age_applicable_income	Passported: 0. Wales with UC: UC earnings before the work allowance + UC unearned income + the award. Otherwise: net earnings − disregards − childcare + unearned income + tariff income (+ relevant UC payments in Scotland).
council_tax_reduction_working_age_person_earned_income, _earned_income, _employed_earned_income	Per claimant/partner. Only the tax and NI in respect of the employment or trade come off earnings (SSI 2021/249 regs 49(6)(b), 50(3)(a); WSI 2013/3029 Sch 6 para 15(3)(a)): the UC model's split of each person's income tax (uc_income_tax_on_earnings, earnings as the lowest slice of non-savings income) and their Class 1, 2 and 4 NI (uc_national_insurance_on_earnings), never Class 3, tax on pensions or tax on dividends. Wales with UC: the UC model's own earned income before the work allowance (uc_individual_earned_income), the Secretary of State's figure (Sch 6 para 9). Scotland with UC: that figure plus SSP/SMP/SPP (reg 49(4)). Without UC: employment and self-employment income plus SSP/SMP/SPP, less half of pension contributions. Employed earnings feed Scotland's £17.10 test.
council_tax_reduction_working_age_unearned_income_tax	Income tax on the counted taxable unearned income: non-savings tax less tax on earnings, shared pro rata with property income. Wales without UC disregards it (Sch 9 para 4); Scotland counts unearned income gross (reg 57).
council_tax_reduction_working_age_earnings_disregard	£25 lone parent; else £20 with a disability premium, or in Scotland for a UC applicant with LCW or LCWRA where one of the couple is under pensionable age and in employment (Sch 3 para 4(3)); else, for a carer, £20 of the carers' own earnings plus up to £10 of a non-carer partner's (paras 6-7; carers identified by a carer benefit in payment); else £10 couple, £5 single. Plus £17.10 on the work conditions (not with UC): a couple's disabled member must be the one in work, and in Scotland from April 2022 only employed earnings qualify. Never more than earnings.
council_tax_reduction_working_age_unearned_income	The closed lists in reg 57(1) and Sch 6 para 17 / Sch 9: pensions, contributory ESA and JSA, carer's allowance, the Carer Support Payment component before the overlapping-benefit reduction, as the pension-age route counts it (not the Scottish Carer Supplement), MA, IIB, IB, SDA, tax credits.
council_tax_reduction_relevant_universal_credit_payments	Scotland: min(child element + disabled-child additions + childcare element, award).
council_tax_reduction_working_age_childcare_deduction	Legacy: charges up to £175 / £300 a week when the lone parent, or both of a couple, work 16 hours or more, taken off earnings after the disregards. Scotland with UC: childcare element ÷ 0.85, up to £290 / £497, taken off income.
council_tax_reduction_working_age_capital, _tariff_income	Wales with UC: UC capital. Wales passported: 0. Otherwise household savings. £1 a week per £250 or part above £6,000.
council_tax_reduction_working_age_passported, _has_universal_credit, _universal_credit_award	IS / JSA(IB) / ESA(IR) without UC; UC entitlement; the award after the benefit cap and before deductions from payment.

The new parameters are under gov.local_authorities.{scotland,wales}.council_tax_reduction.working_age. Every uprated amount has its full history from 2013-14 to 2026-27, and each change cites the amending instrument and provision. The history was compiled from legislation.gov.uk and chain-checked: each year's "for £X" equals the previous year's value. Welsh 2013-14 values, including the fixed disregards, tariff income and childcare caps (from 1 April 2013), come from the revoked WSI 2012/3144, which then applied.

Pension-age CTR, the English schemes and the Housing Benefit parameters are unchanged. Outside the new working_age/ folders, the model code touched is the Scotland/Wales hook in simulated_council_tax_reduction_benunit.py, one docstring in council_tax_reduction_pensioner.py, and the CTR notes in programs.yaml.

council_tax_reduction_pensioner.py is main's file (#1944), with one documentation sentence changed: "the Welsh and Scottish formulas do not yet use it" is no longer true.

Composition with main

The PR is based on main. #1896 has merged, and main has been merged in three times, most recently at 41a996e (main has since gained only a version bump).

• Give sharers, boarders and lodgers their own rent, tenure and LHA category #2006 (joint liability, per-claim scheme). The liability keeps main's council_tax_reduction_joint_liability_share. The working-age route keys on council_tax_reduction_claim_pensioner, the same flag that picks each claim's scheme.
• Disregard guarantee credit recipients' income and capital in pensioner council tax reduction #1909: the non-working-age route keeps council_tax_reduction_assessable_capital.
• Count Carer's Allowance and Carer Support Payment as Pension Credit income #1952: carer_support_payment is now the Carer Support Payment component only, so the earlier supplement subtraction is gone. Like main's CTR income, the working-age route counts carer_support_payment_pre_overlap until it is settled which amount CTR counts.
• Tests from main updated for the law this PR implements:
  • Disregard guarantee credit recipients' income and capital in pensioner council tax reduction #1909's Welsh working-age earner now gets the Welsh allowance and the £5 disregard (£1,111.24, not the HB-based £993.72).
  • Apply the benefit cap to mixed-age couples on Universal Credit, and keep them off pensioner Council Tax Reduction #1944's capped mixed-age UC couple in Wales gets the maximum reduction under WSI 2013/3029 Sch 6 paras 3 and 9. That test's comment had already said so, and it now has a UC maximum amount consistent with its award.
  • My Scottish self-employed case now pays main's Class 4 NI.
  • Three of main's Carer Support Payment cases now run on the devolved route. The Scottish cases also assert the working-age income and amount. The Welsh carer case gets Wales's own £101.85 allowance (W.S.I. 2026/13 reg 11), so £1,260.92 instead of the HB-based £1,195.40. The 2025 Scottish case uses the statutory 2025-26 amounts (SSI 2025/24 reg 16: £92.05 and £46.40, not HB's £92.04 and £46.38; see 2025-26 legacy carer premium and HB personal allowance are extrapolated, not statutory #2110), so £1,173.56 instead of £1,173.25.
• Means-test the Council Tax Reduction applicant and partner, not the benefit unit's claimant #2078 (applicant and partner). Not on main yet. Whichever lands second edits working_age/_applicant.py to read is_council_tax_reduction_applicant_or_partner, then runs its differential property and the Scottish grandmother-head case from its 3 October comment.
• Evaluate claims_all_entitled_benefits per benefit unit #1831 / d046 (take-up) is untouched. In survey runs, CTR claiming is still reported receipt.

Impact (Enhanced FRS 2024-25, real microsimulation runs)

CTR in £bn (recipient households, millions). Base = main 41a996e; this PR = 1e12d2f (the later 8916273 changes only documentation). Enhanced FRS 2024-25 (release 1.56.16), real microsimulation runs. Groups are by the household-head benefit unit's pension status.

Group	2025 base → PR	2026 base → PR	2027 base → PR	2029 base → PR
Scotland, working age	0.044 (0.056) → 0.131 (0.185)	0.045 (0.056) → 0.134 (0.183)	0.048 (0.057) → 0.140 (0.187)	0.052 (0.056) → 0.154 (0.188)
Wales, working age	0.000 (0.001) → 0.009 (0.009)	0.000 (0.001) → 0.009 (0.009)	0.001 (0.003) → 0.010 (0.009)	0.001 (0.003) → 0.012 (0.009)
Scotland, pension age	0.190 (0.237) → 0.190 (0.237)	0.200 (0.239) → 0.200 (0.239)	0.208 (0.239) → 0.208 (0.239)	0.225 (0.241) → 0.225 (0.241)
Wales, pension age	0.014 (0.018) → 0.014 (0.018)	0.016 (0.019) → 0.016 (0.019)	0.017 (0.019) → 0.017 (0.019)	0.021 (0.019) → 0.021 (0.019)
England, pension age	0.654 (0.637) → 0.654 (0.637)	0.696 (0.641) → 0.696 (0.641)	0.738 (0.640) → 0.738 (0.640)	0.839 (0.649) → 0.839 (0.649)
England, working age (reported)	1.346 (2.497) → 1.346 (2.497)	1.357 (2.520) → 1.357 (2.520)	1.371 (2.544) → 1.371 (2.544)	1.387 (2.574) → 1.387 (2.574)
Northern Ireland	0.008 (0.013) → 0.008 (0.013)	0.008 (0.013) → 0.008 (0.013)	0.008 (0.013) → 0.008 (0.013)	0.008 (0.013) → 0.008 (0.013)
UK total CTR	2.256 (3.459) → 2.351 (3.596)	2.322 (3.488) → 2.420 (3.622)	2.390 (3.516) → 2.493 (3.651)	2.533 (3.555) → 2.646 (3.693)

• Change in CTR by year:

  • 2025: £+0.095bn; 0.184m households gain (mean £516 a year); none lose; net income change £+0.095bn
  • 2026: £+0.098bn; 0.156m households gain (mean £627 a year); none lose; net income change £+0.098bn
  • 2027: £+0.102bn; 0.160m households gain (mean £640 a year); under 100 weighted households lose (1 survey record); net income change £+0.102bn
  • 2029: £+0.113bn; 0.160m households gain (mean £705 a year); under 100 weighted households lose (2 survey records); net income change £+0.113bn

• Household net income rises by the same amount as CTR.

• Pension-age CTR in all three countries, English working-age CTR and Northern Ireland are identical to main in every year run.

• Losers. Fewer than 100 weighted households lose in 2027 and 2029, each by under £70 a year. They are Scottish working-age couples without UC who get a disability premium. main's DWP premium parameters project from a 2015 base (uprating.start_instant: 2015-04-01), which overstates 2027 and later amounts. The devolved amounts here project from the 2026-27 law. Set DWP benefit rates to the announced amounts, not CPI projections #1925 removes that start_instant, after which these losses go away.

• Earlier years. The base Enhanced FRS has no weights before 2024. Three YAML cases check the 2015, 2016 and 2018 amounts instead.

Why the gap to reported and official figures remains (data, not law)

Filed as PolicyEngine/policyengine-uk-data#496 and #497 (the fix, policyengine-uk-data#499, lands with the next data release):

• council_tax is the FRS bill net of CTR. DWP defines the FRS 2024-25 CTANNUAL as "Annual CT amount after discounts/reduction", derived from CTREB and CTREBAMT. The model treats it as the gross liability, so each reported recipient's liability is already reduced by its own CTR. 41.5% of Welsh working-age reported recipients have a £0 bill.
  • A diagnostic dataset copy (not a release) adds reported CTR back to FRS-original rows. With this PR on that copy, 2026 CTR is:
    • Scotland working-age: £0.202bn (0.192m households);
    • Wales working-age: £0.045bn (0.036m).
  • On the same copy, main gives £0.075bn and £0.007bn.
• SPI-synthetic rows carry imputed "reported" CTR from the stage-2 QRF. That imputed CTR sits on £78k-£90k earners, and every person in the household carries it.
• Take-up. Only FRS reporters claim CTR in survey runs (Evaluate claims_all_entitled_benefits per benefit unit #1831, d046). Wales has 0.056m FRS-original working-age reporters, against 157k working-age CTR households in March 2026.

Group, 2026	This PR, release data	This PR, gross-bill diagnostic data	FRS reported	Official
Scotland, working age	£0.134bn (0.183m)	£0.202bn (0.192m)	£0.134bn (0.343m)	about £0.276bn and 306,740 recipients (March 2026)¹
Wales, working age	£0.009bn (0.009m)	£0.045bn (0.036m)	£0.072bn (0.111m)	157,021 households (March 2026); all ages £347.4m (2025-26), £336.0m budgeted (2026-27)²
England, pension age	£0.696bn (0.641m)	£0.998bn (0.784m)	£0.518bn (1.169m)	£1.816bn forgone (2025-26), 1,349,524 claimants (31 March 2026)³

1. Council Tax Reduction in Scotland, 2025-26 (gov.scot):
   • £425.1m provisional income forgone in 2025-26; 458,950 recipients in March 2026.
   • Working-age recipients = the total less pension-age recipients (sheet 2.6).
   • £0.276bn is the under-65 share of the £425.1m, derived from the average weekly awards by age (sheet 3.3). No split by age is published.
2. Welsh Government, Council Tax Reduction Scheme annual report 2025 to 2026; StatsWales revenue budget (CTRS) 2026-27.
3. MHCLG Council Taxbase 2025, CT Support sheet; Local Council Tax Support claimants live table, Q1 2026-27.

Not modelled (documented in the variables)

• Components and premium conditions. The ESA work-related activity and support components are not modelled, and the disability premium's LCW/LCWRA exclusion is not applied. Who qualifies for the adult premiums follows the model's legacy premium variables (Give pension-age HB and CTR the severe disability premium Pension Credit uses #1938 and Give the legacy severe disability premium its statutory conditions (stacked on #1896) #1946 are revising their conditions); the amounts are the devolved ones.
• Tax credits. The childcare deduction's extension to earnings plus WTC/CTC, and the up-to-£17.10 WTC disregard, are not modelled; tax credits ended in April 2025.
• Mid-year changes. Amounts that change mid-year (for example the Scottish UC childcare caps from 28 June 2023) apply from the next model year, because the model samples one value a year.
• Scottish fixed amounts before SSI 2021/249. Scotland's disregards, tariff income, childcare caps and hours parameters cite SSI 2021/249 from 2013; the predecessor SSI 2012/303 is not separately cited, and Scotland's April-September 2013 tariff-income threshold for applicants aged 60 or over is not modelled. (Wales's fixed amounts cite WSI 2012/3144 for 2013-14.)
• Statutory pay on the Welsh UC route. The Welsh UC route uses the UC model's own earned income, as Sch 6 para 9 requires, so it inherits that model's omission of SSP/SMP/SPP from UC earnings (UC Regs 2013 reg 55(4)); both the UC award and CTR leave them out. A separate fix to the UC model will carry through automatically, and a differential test keeps the two in step.
• Scottish carer premium with no carer benefit in payment. The carer earnings disregard identifies carers by a carer benefit in payment (Sch 3 para 6(1)(a)). Where a Scottish family has the carer premium but no one receives Carer's Allowance or Carer Support Payment (an award of UC with the carer element, or a carer benefit overlapped to nil), the £20 is approximated against the family's earnings. That can exceed Sch 3 para 7's £10 limit on a non-carer partner's earnings.
• Transitional family premium. Scotland's is not modelled, because the model cannot see an unbroken claim since May 2016.
• Scotland-only routes. The band E-H alternative maximum (reg 14) and the second adult rebate are not modelled.
• Scotland before April 2022. Its UC rules under SSI 2012/303 are approximated with the 2021 scheme's structure. The UC childcare caps before 2022 take the 2022 value (£175 / £300), the same as the non-UC caps.
• Exclusions. Students and persons from abroad are not excluded.
• Non-dependant deductions still use Housing Benefit amounts, with no exemptions. That is National council tax reduction: non-dependant deductions use Housing Benefit amounts and skip exemptions; pensioner gate ignores benefit exclusions #1934, a separate PR to follow.
• Capital is household savings (Pensioners without Pension Credit are tested on household savings only for the council tax reduction capital limit #1936).

Tests

• YAML. council_tax_reduction_devolved_working_age.yaml has 32 cases. Expected values are worked by hand from the law's amounts:
  • Wales UC with no earnings: full award;
  • Wales UC excess income = 0.45 × earnings with no work allowance;
  • the Wales UC award is the same at double the rent;
  • a Welsh couple with a child and no UC (Sch 7 amounts, disregards, Child Benefit ignored);
  • a Scottish UC lone parent counting only the child element;
  • a Scottish UC single earner (the £5 disregard, and no UC counted);
  • the Scottish under-25 allowance;
  • the ESA passport in both countries;
  • Scotland's capital limit for a passported claimant;
  • tariff income;
  • a mixed-age UC couple in Wales on the working-age route;
  • 2015-16, 2016-17 and 2018-19 amounts;
  • regressions for the first review round: the carer disregard, the £17.10 conditions, Welsh tax on unearned income, the CSP component, a carer premium per partner, SMP on the Scottish UC route, the 2025 Scottish disability premium;
  • regressions for the second review round: tax on a pension or on dividends never comes off wages (three Welsh cases, one Scottish), a Welsh carer premium on entitlement when contributory ESA overlaps Carer's Allowance to nil, no Scottish carer premium from a potential UC carer element, the Scottish UC LCWRA £20 disregard, and voluntary Class 3 NI.
• Property and differential tests. test_council_tax_reduction_devolved_working_age_properties.py runs many households in one simulation:
  • Hypothesis: 0 ≤ award ≤ liability; the Wales UC award does not depend on rent (uncapped awards); the UC award never rises with earnings; IS/JSA/ESA passported claimants get the full liability.
  • Differential: on the Welsh UC route, CTR earnings equal the UC model's uc_individual_earned_income, income equals earnings + uc_unearned_income + the award, and the applicable amount equals uc_maximum_amount, with and without SMP.
  • A targeted partial Welsh UC award (£246.36) that is the same at £6,000 and £13,000 rent.
  • Wales's fixed amounts start on 1 April 2013 with the WSI 2012/3144 values.
• Mutation checks, each run against these tests:
  • Removing the Welsh UC income route fails the differential test and the targeted partial-award test. The 20 derandomised Hypothesis examples alone do not catch it, which is why the targeted case was added.
  • Removing the passport fails the passport property.
  • Reverting each second-round fix fails its regression: all tax off wages (4 cases fail), Class 3 off wages, the carer premium on receipt, the potential UC carer element, dropping the LCWRA limb, and adding statutory pay to Welsh UC earnings (the differential test fails).
• Outsider income. test_means_test_income_properties.py now also checks that the new working-age income never counts income from people outside the family.
• Suites. Locally at 8916273: the CTR YAML directory, 149 passed; the two property files, 6 passed. CI runs the full suite on this PR.

Invariants

• 0 ≤ award ≤ liability.
• The award is non-increasing in earnings on the UC route.
• A Welsh UC award is independent of the housing costs element when there is no benefit cap.
• A passported claimant gets the full liability less non-dependant deductions.
• On the Welsh UC route, CTR earnings equal the UC model's earned income, so CTR and UC never disagree on earnings.
• Pension-age CTR is identical to the base in every year run.

Effect on pensioner CTR (uk-triple-lock)

None. Pension-age CTR in England, Scotland and Wales is identical to main (41a996e) in every year run (2025, 2026, 2027 and 2029), so uk-triple-lock's pensioner offsets are unaffected.

The one legal change on the pension side is that a mixed-age couple on UC in Scotland or Wales takes the working-age route, keyed on main's council_tax_reduction_claim_pensioner (WSI 2013/3029 reg 3; SSI 2021/249 reg 3). The pension-age totals above are unchanged with it.

🤖 Generated with Claude Code

[MaxGhenis]

Coordination note from #1992 (Scottish CTR counts Carer Support Payment, stacked on #1952).

council_tax_reduction_working_age_unearned_income here subtracts carer_support_payment × supplement / (rate + supplement). That assumes carer_support_payment includes the Scottish Carer Supplement, which is true on main today. #1952 makes carer_support_payment the CSP component only (csp.rate × 52) and adds a separate scottish_carer_supplement.

Once #1952 is in, this subtraction would remove £535.88 a year of genuine CSP in 2026 (4,495.40 × 11.70 / 98.15), understating income for every Scottish working-age carer. Whichever of #1952 and this PR merges second should drop the subtraction and count carer_support_payment as it stands.

The carers overlapping-benefits work (#1953) will also make carer_support_payment the amount payable after CSP Regs reg 16(2). SSI 2021/249 reg 57(1)(b) counts benefits "subject to any adjustment … under section 73 of the Social Security Administration Act 1992"; whether that covers a reg 16(2) reduction is being checked in #1992.

🤖 Generated with Claude Code

[MaxGhenis]

Composition note: #2015 (stacked on #2009 → #2006) adds council_tax_reduction_pensioner (BenUnit) with the same name, entity and meaning as this PR, but only the age test, and deletes council_tax_reduction_household_has_pensioner. Every CTR scheme now reads the per-family flag: national, the four _legacy councils, Oxford and council_tax_reduction_scheme_supported. Whichever lands second: keep this PR's formula for council_tax_reduction_pensioner.py (add/add), delete council_tax_reduction_household_has_pensioner.py (modify/delete), and change any remaining benunit.household("council_tax_reduction_household_has_pensioner", period) to benunit("council_tax_reduction_pensioner", period).

[MaxGhenis]

Composition note from #2078 (stacked on #2009), which makes the CTR means test assess the applicant and partner rather than the benefit unit's claimant and partner.

#2078 adds is_council_tax_reduction_applicant_or_partner (Person): the benefit unit's claimant and partner where the liable person is one of them, and the household head alone where the head is liable but is not the benefit unit's claimant or partner (council_tax_reduction_head_applies_alone; for example, a grandmother head sharing a benefit unit with a young couple who are its claimant and partner).

council_tax_reduction_pensioner here reads the generic claimant identity. Whichever of the two PRs lands second should make it read is_council_tax_reduction_applicant_or_partner. Otherwise the 80-year-old grandmother above, whose benefit unit's claimant and partner are 17, is not a pensioner and goes on a working-age scheme. SI 2012/2885 reg 3(1)(a)(i): "he has attained the qualifying age for state pension credit", where "he" is the applicant. #2078 already does this for council_tax_reduction_household_has_pensioner; its YAML case "A pensioner who is not the applicant or partner does not make a young couple's claim a pensioner's" pins it.

[MaxGhenis]

Correction to my earlier note, from #2078's review r1. A pensioner-flag swap is not enough for #1966, because it adds its own working-age assessment.

#2078 (now stacked on #2015) makes the CTR means test assess the applicant and partner (is_council_tax_reduction_applicant_or_partner), not the benefit unit's claimant and partner. Where the household head is liable but is not the benefit unit's claimant or partner (council_tax_reduction_head_applies_alone; for example a grandmother sharing a benefit unit with a young couple), the head applies alone: a single person, with the benefit unit's awards and children belonging to the couple.

#1966's working-age assessment has its own person masks and family tests. Whichever of #1966 and #2078 lands second must move all of them onto the applicant identity:

• unearned income (council_tax_reduction_working_age_unearned_income) and earned income;
• family status and children;
• premiums;
• the passport;
• the Universal Credit route.

Then run #2078's differential property (test_head_applying_alone_matches_her_own_benefit_unit) on the composed tree, plus one case: Scotland 2026, a 40-year-old head with a £100,000 private pension, sharing a benefit unit with two 17-year-old parents and their baby, £1,800 council tax. SSI 2021/249 reg 36 counts her pension, so she gets no reduction. With only the pensioner swap, #1966's reader would leave it out and pay £1,800.

[MaxGhenis]

Status, paused by Fleet ops (overnight session cap): head a5e5a73 is based on main, MERGEABLE, CI running. CTR YAML 129 passed; property tests pass.

Pending:

• Review. Hard-tier review, subfleet run 20261003-221336-ctr1966-review-r2. Output goes to ~/reviews/uk-ctr-shortfall-2026-09-30/out/review_r2_a5e5a73.md.
• Impact. The rerun against main 7fee075 is impact/branch_a5e5a73.json beside impact/base_main_2efc8d8.json.

Next: read the review and fix anything it finds, update the PR's impact table, mark ready, and merge on gates or hand off to the UK hub.

🤖 Generated with Claude Code

[MaxGhenis]

A note from #2288, which gives Scotland's working-age Council Tax Reduction scheme its own "young person" (SSI 2021/249 reg. 6(1): the Universal Credit qualifying young person, UC Regs 2013 reg. 5) and leaves England, Wales and Scotland's pension-age scheme on the Child Benefit one.

When this PR is rebased after #2288 lands, five reads in the new working-age variables use the legacy flags, which follow the Child Benefit definition:

File (at this PR's head)	Line	Reads
working_age/council_tax_reduction_working_age_child_amounts.py	44	is_child_or_young_person_for_legacy_benefits
working_age/council_tax_reduction_working_age_childcare_deduction.py	47	is_child_or_young_person_for_legacy_benefits
working_age/council_tax_reduction_working_age_earnings_disregard.py	66	is_lone_parent
working_age/council_tax_reduction_working_age_earnings_disregard.py	153	is_child_or_young_person_for_legacy_benefits
working_age/council_tax_reduction_working_age_personal_allowance.py	38	is_lone_parent

For Scotland these should read is_child_or_young_person_for_council_tax_reduction and is_council_tax_reduction_lone_parent from #2288. Those already choose the definition by scheme (Universal Credit for Scottish working-age families from 2022-23, Child Benefit everywhere else), so Wales is unaffected by switching to them. The two definitions differ for a 19-year-old on a course begun before 19 who is past the 1 September after their 19th birthday: a Child Benefit young person until 20, not a Universal Credit one.

#2288 also edits council_tax_reduction_applicable_amount (lines 25 to 27 here) and the income mask in council_tax_reduction_applicable_income (line 43 here), so those two files will conflict. The severe disability premium has the same issue through a shared helper: #2295.