Stop discounting LTT and LBTT twice

changelog.d/2246.fixed.md

@@ -0,0 +1 @@
+- Stop discounting Land Transaction Tax and Land and Buildings Transaction Tax twice. `expected_ltt` and `expected_lbtt` multiplied `land_transaction_tax` and `land_and_buildings_transaction_tax` by `gov.hmrc.stamp_duty.property_sale_rate` (0.045), but those liabilities are already charged only on the year's purchases and rent increments. Each expected value now equals its liability, the convention `expected_sdlt` follows, so `gov_tax`, `household_tax` and `pre_budget_change_household_tax` count LTT and LBTT at their full value and LTT or LBTT reforms are scored at full value rather than 4.5% of it.

changelog.d/2246.removed.md

@@ -0,0 +1 @@
+- Remove `gov.hmrc.stamp_duty.property_sale_rate`, a 2021 placeholder with no remaining reader once `expected_sdlt`, `expected_ltt` and `expected_lbtt` stopped scaling by it. A reform that sets it now raises an unknown-parameter error instead of silently doing nothing.

policyengine_uk/data/fiscal_partition.yaml

@@ -368,8 +368,12 @@ tax_heads:
     totals: [gov_tax, household_tax, pre_budget_change_household_tax]
     sign: nonnegative
     data_note: >-
-      expected_ltt multiplies an already purchase-drawn liability by
-      property_sale_rate, discounting it twice (issue 2246).
+      Equal to land_transaction_tax, with no property sale rate scaling
+      (issue 2246). On policyengine-uk-data 1.58.0 (enhanced_frs_2024_25),
+      £0.070bn in 2026, all on main-residence purchases: no Welsh record has
+      an additional-dwelling or non-residential purchase or a rent charge.
+      Measured 2026-10-11. The main residential schedule predates the 10
+      October 2022 bands (issue 1796).
   - id: land_and_buildings_transaction_tax
     label: Land and buildings transaction tax (Scotland)
     variable: expected_lbtt
@@ -381,8 +385,12 @@ tax_heads:
     totals: [gov_tax, household_tax, pre_budget_change_household_tax]
     sign: nonnegative
     data_note: >-
-      expected_lbtt multiplies an already purchase-drawn liability by
-      property_sale_rate, discounting it twice (issue 2246).
+      Equal to land_and_buildings_transaction_tax, with no property sale rate
+      scaling (issue 2246). On policyengine-uk-data 1.58.0
+      (enhanced_frs_2024_25) in 2026, £0.385bn on main-residence purchases.
+      Before PR 2241 (issue 2238) it is £2.310bn: the main-residence purchase
+      flag also charges £15.2bn of other residential property as
+      additional-dwelling purchases. Measured 2026-10-11.
 
   # Reform-only heads
   - id: corporate_incident_tax_change
@@ -467,14 +475,14 @@ exclusions:
   - {variable: sdlt_on_non_residential_property_transactions, kind: component, head: sdlt_household}
   - {variable: sdlt_on_residential_property_rent, kind: component, head: sdlt_household}
   - {variable: sdlt_on_non_residential_property_rent, kind: component, head: sdlt_household}
-  - {variable: land_transaction_tax, kind: component, head: land_transaction_tax, note: "The liability before the property_sale_rate scaling (issue 2246)."}
+  - {variable: land_transaction_tax, kind: component, head: land_transaction_tax, note: "Equal to expected_ltt (issue 2246); report the head, not this."}
   - {variable: ltt_on_transactions, kind: component, head: land_transaction_tax}
   - {variable: ltt_on_rent, kind: component, head: land_transaction_tax}
   - {variable: ltt_on_residential_property_transactions, kind: component, head: land_transaction_tax}
   - {variable: ltt_on_non_residential_property_transactions, kind: component, head: land_transaction_tax}
   - {variable: ltt_on_residential_property_rent, kind: component, head: land_transaction_tax}
   - {variable: ltt_on_non_residential_property_rent, kind: component, head: land_transaction_tax}
-  - {variable: land_and_buildings_transaction_tax, kind: component, head: land_and_buildings_transaction_tax, note: "The liability before the property_sale_rate scaling (issue 2246)."}
+  - {variable: land_and_buildings_transaction_tax, kind: component, head: land_and_buildings_transaction_tax, note: "Equal to expected_lbtt (issue 2246); report the head, not this."}
   - {variable: lbtt_on_transactions, kind: component, head: land_and_buildings_transaction_tax}
   - {variable: lbtt_on_rent, kind: component, head: land_and_buildings_transaction_tax}
   - {variable: lbtt_on_residential_property_transactions, kind: component, head: land_and_buildings_transaction_tax}

policyengine_uk/tests/policy/baseline/gov/hmrc/council_tax/high_value_council_tax_surcharge.yaml

@@ -72,7 +72,6 @@
     main_residential_property_purchased: 0
     council_tax: 0
     household_owns_tv: false
-    gov.hmrc.stamp_duty.property_sale_rate: 0
   output:
     high_value_council_tax_surcharge: 2_500
     household_tax: 2_500
@@ -85,7 +84,6 @@
     main_residential_property_purchased: 0
     council_tax: 0
     household_owns_tv: false
-    gov.hmrc.stamp_duty.property_sale_rate: 0
   output:
     high_value_council_tax_surcharge: 0
     household_tax: 0
@@ -99,7 +97,6 @@
     main_residential_property_purchased: 0
     council_tax: 0
     household_owns_tv: false
-    gov.hmrc.stamp_duty.property_sale_rate: 0
   output:
     high_value_council_tax_surcharge: 0
 - name: Housing association tenants owe nothing
@@ -111,7 +108,6 @@
     main_residential_property_purchased: 0
     council_tax: 0
     household_owns_tv: false
-    gov.hmrc.stamp_duty.property_sale_rate: 0
   output:
     high_value_council_tax_surcharge: 0
 - name: A household with no tenure supplied takes the RENT_PRIVATELY default and owes nothing
@@ -122,7 +118,6 @@
     main_residential_property_purchased: 0
     council_tax: 0
     household_owns_tv: false
-    gov.hmrc.stamp_duty.property_sale_rate: 0
   output:
     high_value_council_tax_surcharge: 0
 - name: Ownership condition holds when a reform lowers the first threshold to £1.5m (owner)
@@ -135,7 +130,6 @@
     main_residential_property_purchased: 0
     council_tax: 0
     household_owns_tv: false
-    gov.hmrc.stamp_duty.property_sale_rate: 0
   output:
     high_value_council_tax_surcharge: 2_500
 - name: Ownership condition holds when a reform lowers the first threshold to £1.5m (private renter)
@@ -148,6 +142,5 @@
     main_residential_property_purchased: 0
     council_tax: 0
     household_owns_tv: false
-    gov.hmrc.stamp_duty.property_sale_rate: 0
   output:
     high_value_council_tax_surcharge: 0

policyengine_uk/tests/policy/baseline/gov/revenue_scotland/expected_lbtt.yaml

@@ -0,0 +1,147 @@
+# expected_lbtt is the household's own LBTT, with no further scaling (issue 2246).
+#
+# Residential rates: The Land and Buildings Transaction Tax (Tax Rates and Tax
+# Bands) (Scotland) Order 2015 (SSI 2015/126) schedule, Table A, in force again
+# from 1 April 2021 (the temporary nil band in SSI 2020/215 art. 2 ran to the end
+# of 31 March 2021): 0% to £145,000; 2% to £250,000; 5% to £325,000; 10% to
+# £750,000; 12% above.
+#   https://www.legislation.gov.uk/ssi/2015/126/schedule/made
+# First-time buyer relief: tax is not chargeable on the first £175,000
+# (Land and Buildings Transaction Tax (Scotland) Act 2013 schedule 4A para 3).
+#   https://www.legislation.gov.uk/asp/2013/11/schedule/4A
+# Non-residential rates: SSI 2015/126 schedule, Table B as substituted by SSI
+# 2018/372 from 25 January 2019: 0% to £150,000; 1% to £250,000; 5% above.
+#   https://www.legislation.gov.uk/ssi/2015/126/schedule
+- name: No purchase means no LBTT in the tax totals (Scotland)
+  period: 2026
+  absolute_error_margin: 0
+  input:
+    region: SCOTLAND
+    council_tax: 0
+    household_owns_tv: false
+  output:
+    land_and_buildings_transaction_tax: 0
+    expected_lbtt: 0
+    household_tax: 0
+    gov_tax: 0
+- name: Expected LBTT on a main-residence purchase equals the LBTT liability
+  # £400,000, not a first home:
+  # 2% x (250,000 - 145,000) = 2,100
+  # 5% x (325,000 - 250,000) = 3,750
+  # 10% x (400,000 - 325,000) = 7,500
+  # Total 13,350.
+  period: 2026
+  absolute_error_margin: 0
+  input:
+    region: SCOTLAND
+    main_residential_property_purchased: 400_000
+    main_residential_property_purchased_is_first_home: false
+    council_tax: 0
+    household_owns_tv: false
+  output:
+    lbtt_on_residential_property_transactions: 13_350
+    land_and_buildings_transaction_tax: 13_350
+    expected_lbtt: 13_350
+    household_tax: 13_350
+    gov_tax: 13_350
+    pre_budget_change_household_tax: 13_350
+- name: Expected LBTT on a purchase above £750,000 includes the 12% band
+  # £1,000,000, not a first home:
+  # 2,100 + 3,750 + 10% x (750,000 - 325,000) = 42,500
+  # + 12% x (1,000,000 - 750,000) = 30,000
+  # Total 78,350.
+  period: 2026
+  absolute_error_margin: 0
+  input:
+    region: SCOTLAND
+    main_residential_property_purchased: 1_000_000
+    main_residential_property_purchased_is_first_home: false
+    council_tax: 0
+    household_owns_tv: false
+  output:
+    land_and_buildings_transaction_tax: 78_350
+    expected_lbtt: 78_350
+    gov_tax: 78_350
+- name: A purchase at the top of the nil band pays no LBTT
+  period: 2026
+  absolute_error_margin: 0
+  input:
+    region: SCOTLAND
+    main_residential_property_purchased: 145_000
+    main_residential_property_purchased_is_first_home: false
+    council_tax: 0
+    household_owns_tv: false
+  output:
+    land_and_buildings_transaction_tax: 0
+    expected_lbtt: 0
+    gov_tax: 0
+- name: A purchase at the top of the 2% band pays 2% of the band
+  # 2% x (250,000 - 145,000) = 2,100.
+  period: 2026
+  absolute_error_margin: 0
+  input:
+    region: SCOTLAND
+    main_residential_property_purchased: 250_000
+    main_residential_property_purchased_is_first_home: false
+    council_tax: 0
+    household_owns_tv: false
+  output:
+    land_and_buildings_transaction_tax: 2_100
+    expected_lbtt: 2_100
+    gov_tax: 2_100
+- name: First-time buyer relief takes the first £175,000 out of charge
+  # £200,000 first home: 2% x (200,000 - 175,000) = 500.
+  period: 2026
+  absolute_error_margin: 0
+  input:
+    region: SCOTLAND
+    main_residential_property_purchased: 200_000
+    main_residential_property_purchased_is_first_home: true
+    council_tax: 0
+    household_owns_tv: false
+  output:
+    land_and_buildings_transaction_tax: 500
+    expected_lbtt: 500
+    household_tax: 500
+    gov_tax: 500
+- name: Expected LBTT on a non-residential purchase equals the LBTT liability
+  # £300,000: 1% x (250,000 - 150,000) = 1,000
+  # 5% x (300,000 - 250,000) = 2,500
+  # Total 3,500.
+  period: 2026
+  absolute_error_margin: 0
+  input:
+    region: SCOTLAND
+    non_residential_property_purchased: 300_000
+    council_tax: 0
+    household_owns_tv: false
+  output:
+    lbtt_on_non_residential_property_transactions: 3_500
+    land_and_buildings_transaction_tax: 3_500
+    expected_lbtt: 3_500
+    household_tax: 3_500
+    gov_tax: 3_500
+- name: No LBTT outside Scotland, even on a purchase (Wales)
+  period: 2026
+  absolute_error_margin: 0
+  input:
+    region: WALES
+    main_residential_property_purchased: 400_000
+    main_residential_property_purchased_is_first_home: false
+    council_tax: 0
+    household_owns_tv: false
+  output:
+    land_and_buildings_transaction_tax: 0
+    expected_lbtt: 0
+- name: No LBTT outside Scotland, even on a purchase (England)
+  period: 2026
+  absolute_error_margin: 0
+  input:
+    region: LONDON
+    main_residential_property_purchased: 400_000
+    main_residential_property_purchased_is_first_home: false
+    council_tax: 0
+    household_owns_tv: false
+  output:
+    land_and_buildings_transaction_tax: 0
+    expected_lbtt: 0

policyengine_uk/tests/policy/baseline/gov/wra/land_transaction_tax/expected_ltt.yaml

@@ -0,0 +1,137 @@
+# expected_ltt is the household's own LTT, with no further scaling (issue 2246).
+#
+# Rates: The Land Transaction Tax (Tax Bands and Tax Rates) (Wales) Regulations
+# 2018 (WSI 2018/128) schedule.
+# - Table 1, main residential rates, as at 1 January 2022 (the model samples
+#   2022 at 30 April 2022, before the 10 October 2022 substitution by WSI
+#   2022/1027): 0% to £180,000; 3.5% to £250,000; 5% to £400,000; 7.5% to
+#   £750,000; 10% to £1,500,000; 12% above.
+#   https://www.legislation.gov.uk/wsi/2018/128/schedule/2022-01-01
+#   The model's main residential schedule still has these bands after 10
+#   October 2022 (issue 1796), so the residential cases are in 2022.
+# - Table 2, higher rates, as substituted by WSI 2020/1618 and in force on 30
+#   April 2022: 4% to £180,000; 7.5% to £250,000; 9% to £400,000; 11.5% to
+#   £750,000; 14% to £1,500,000; 16% above.
+# - Table 3, non-residential rates, as substituted by WSI 2020/1618 and still
+#   in force: 0% to £225,000; 1% to £250,000; 5% to £1,000,000; 6% above.
+#   https://www.legislation.gov.uk/wsi/2018/128/schedule
+- name: No purchase means no LTT in the tax totals (Wales)
+  period: 2026
+  absolute_error_margin: 0
+  input:
+    region: WALES
+    council_tax: 0
+    household_owns_tv: false
+  output:
+    land_transaction_tax: 0
+    expected_ltt: 0
+    household_tax: 0
+    gov_tax: 0
+- name: Expected LTT on a main-residence purchase equals the LTT liability
+  # £300,000 in 2022:
+  # 3.5% x (250,000 - 180,000) = 2,450
+  # 5% x (300,000 - 250,000) = 2,500
+  # Total 4,950.
+  period: 2022
+  absolute_error_margin: 0
+  input:
+    region: WALES
+    main_residential_property_purchased: 300_000
+    council_tax: 0
+    household_owns_tv: false
+  output:
+    ltt_on_residential_property_transactions: 4_950
+    land_transaction_tax: 4_950
+    expected_ltt: 4_950
+    household_tax: 4_950
+    gov_tax: 4_950
+    pre_budget_change_household_tax: 4_950
+- name: Expected LTT on a main-residence purchase above £1.5m includes the 12% band
+  # £2,000,000 in 2022:
+  # 2,450 + 5% x (400,000 - 250,000) = 7,500
+  # + 7.5% x (750,000 - 400,000) = 26,250
+  # + 10% x (1,500,000 - 750,000) = 75,000
+  # + 12% x (2,000,000 - 1,500,000) = 60,000
+  # Total 171,200.
+  period: 2022
+  absolute_error_margin: 0
+  input:
+    region: WALES
+    main_residential_property_purchased: 2_000_000
+    council_tax: 0
+    household_owns_tv: false
+  output:
+    land_transaction_tax: 171_200
+    expected_ltt: 171_200
+    gov_tax: 171_200
+- name: A purchase at the top of the zero rate band pays no LTT
+  period: 2022
+  absolute_error_margin: 0
+  input:
+    region: WALES
+    main_residential_property_purchased: 180_000
+    council_tax: 0
+    household_owns_tv: false
+  output:
+    land_transaction_tax: 0
+    expected_ltt: 0
+    gov_tax: 0
+- name: Expected LTT on an additional-dwelling purchase equals the higher-rates liability
+  # £200,000 in 2022 at the higher rates:
+  # 4% x 180,000 = 7,200
+  # 7.5% x (200,000 - 180,000) = 1,500
+  # Total 8,700.
+  period: 2022
+  absolute_error_margin: 0
+  input:
+    region: WALES
+    additional_residential_property_purchased: 200_000
+    council_tax: 0
+    household_owns_tv: false
+  output:
+    ltt_on_residential_property_transactions: 8_700
+    land_transaction_tax: 8_700
+    expected_ltt: 8_700
+    household_tax: 8_700
+    gov_tax: 8_700
+- name: Expected LTT on a non-residential purchase equals the LTT liability
+  # £1,200,000 in 2026:
+  # 1% x (250,000 - 225,000) = 250
+  # 5% x (1,000,000 - 250,000) = 37,500
+  # 6% x (1,200,000 - 1,000,000) = 12,000
+  # Total 49,750.
+  period: 2026
+  absolute_error_margin: 0
+  input:
+    region: WALES
+    non_residential_property_purchased: 1_200_000
+    council_tax: 0
+    household_owns_tv: false
+  output:
+    ltt_on_non_residential_property_transactions: 49_750
+    land_transaction_tax: 49_750
+    expected_ltt: 49_750
+    household_tax: 49_750
+    gov_tax: 49_750
+- name: No LTT outside Wales, even on a purchase (Scotland)
+  period: 2026
+  absolute_error_margin: 0
+  input:
+    region: SCOTLAND
+    non_residential_property_purchased: 1_200_000
+    council_tax: 0
+    household_owns_tv: false
+  output:
+    land_transaction_tax: 0
+    expected_ltt: 0
+- name: No LTT outside Wales, even on a purchase (England)
+  period: 2026
+  absolute_error_margin: 0
+  input:
+    region: LONDON
+    non_residential_property_purchased: 1_200_000
+    council_tax: 0
+    household_owns_tv: false
+  output:
+    land_transaction_tax: 0
+    expected_ltt: 0