Add Montana state supplementation for 2026

changelog.d/mt-ssp.added.md

@@ -0,0 +1 @@
+Add Montana optional State Supplementary Payments with income phaseout, couple and deeming calculations, verified for 2026, and count them in Montana elderly homeowner or renter credit gross household income.

policyengine_us/parameters/gov/household/household_state_benefits.yaml

@@ -17,6 +17,7 @@ values:
     - mo_child_care_subsidies
     # Montana benefits
     - mt_child_care_subsidies
+    - mt_ssp
     # Massachusetts benefits
     - ma_state_supplement
     # Maryland benefits
@@ -118,6 +119,7 @@ values:
     - mo_child_care_subsidies
     # Montana benefits
     - mt_child_care_subsidies
+    - mt_ssp
     # Massachusetts benefits
     - ma_state_supplement
     # Maryland benefits
@@ -228,6 +230,7 @@ values:
     - mo_child_care_subsidies
     # Montana benefits
     - mt_child_care_subsidies
+    - mt_ssp
     # Massachusetts benefits
     - ma_state_supplement
     # Maryland benefits
@@ -339,6 +342,7 @@ values:
     - mo_child_care_subsidies
     # Montana benefits
     - mt_child_care_subsidies
+    - mt_ssp
     # Massachusetts benefits
     - ma_state_supplement
     # Maryland benefits

policyengine_us/parameters/gov/hud/annual_income/sources/unearned.yaml

@@ -24,6 +24,7 @@ values:
     - wy_ssp
     - nc_sa_countable_for_hud
     - nv_oss
+    - mt_ssp
     - general_assistance
     - total_unemployment_compensation
     - child_support_received

policyengine_us/parameters/gov/states/mt/dphhs/ssp/amount/couple.yaml

@@ -0,0 +1,36 @@
+description: Montana provides these amounts as the monthly couple payment under the State Supplementary Payment program.
+
+metadata:
+  unit: currency-USD
+  period: month
+  label: Montana SSP couple payment amount
+  breakdown:
+    - mt_ssp_payment_category
+  reference:
+    - title: POMS SI 01415.058 H.2.b, Montana couple payment levels (January 2026)
+      href: https://secure.ssa.gov/poms.nsf/lnx/0501415058#h2b
+    - title: POMS SI DEN01415.010 B.6, Montana supplementary payment categories
+      href: https://secure.ssa.gov/poms.nsf/lnx/0501415010DEN
+    - title: MCA 52-1-104(1)-(3)
+      href: https://mca.legmt.gov/bills/mca/title_0520/chapter_0010/part_0010/section_0040/0520-0010-0010-0040.html
+
+# POMS codes G, H and I.
+ASSISTED_LIVING_OR_GROUP_OR_COMMUNITY_HOME:
+  2026-01-01: 193
+
+# POMS code J.
+FOSTER_CARE:
+  2026-01-01: 110.5
+
+# POMS code K.
+TRANSITIONAL_LIVING:
+  2026-01-01: 57
+
+# MCA 52-1-104(3) bars payments to category B assisted living residents.
+CATEGORY_B_ASSISTED_LIVING:
+  2026-01-01: 0
+
+# No certified placement, POMS SI 01415.058 H.1 code Z (not certified in codes
+# G-K); also the default for people outside Montana.
+NONE:
+  2026-01-01: 0

policyengine_us/parameters/gov/states/mt/dphhs/ssp/amount/individual.yaml

@@ -0,0 +1,36 @@
+description: Montana provides these amounts as the monthly individual payment under the State Supplementary Payment program.
+
+metadata:
+  unit: currency-USD
+  period: month
+  label: Montana SSP individual payment amount
+  breakdown:
+    - mt_ssp_payment_category
+  reference:
+    - title: POMS SI 01415.058 H.2.a, Montana individual payment levels (January 2026)
+      href: https://secure.ssa.gov/poms.nsf/lnx/0501415058#h2a
+    - title: POMS SI DEN01415.010 B.6, Montana supplementary payment categories
+      href: https://secure.ssa.gov/poms.nsf/lnx/0501415010DEN
+    - title: MCA 52-1-104(1)-(3)
+      href: https://mca.legmt.gov/bills/mca/title_0520/chapter_0010/part_0010/section_0040/0520-0010-0010-0040.html
+
+# POMS codes G, H and I.
+ASSISTED_LIVING_OR_GROUP_OR_COMMUNITY_HOME:
+  2026-01-01: 94
+
+# POMS code J.
+FOSTER_CARE:
+  2026-01-01: 52.75
+
+# POMS code K.
+TRANSITIONAL_LIVING:
+  2026-01-01: 26
+
+# MCA 52-1-104(3) bars payments to category B assisted living residents.
+CATEGORY_B_ASSISTED_LIVING:
+  2026-01-01: 0
+
+# No certified placement, POMS SI 01415.058 H.1 code Z (not certified in codes
+# G-K); also the default for people outside Montana.
+NONE:
+  2026-01-01: 0

policyengine_us/parameters/gov/states/mt/tax/income/credits/elderly_homeowner_or_renter/gross_income_sources.yaml

@@ -60,6 +60,9 @@ values:
     # so the household sum counts the unit's TANF once. LIEAP and SNAP are
     # not cash public assistance (2014-2017 Form 2EC instructions).
     - ssi
+    # § 15-30-2337(9)(a)(vi) – the Montana State Supplementary Payment is
+    # nontaxable cash public assistance paid with SSI; ssi excludes it.
+    - mt_ssp
     - tanf_person
     - workers_compensation
     # Guaranteed income pilot payments are outside federal AGI here, and
@@ -97,6 +100,7 @@ values:
     - strike_benefits
     - general_assistance
     - ssi
+    - mt_ssp
     - tanf_person
     - workers_compensation
     - gi_cash_assistance
@@ -119,6 +123,7 @@ values:
     - strike_benefits
     - general_assistance
     - ssi
+    - mt_ssp
     - tanf_person
     - workers_compensation
     - gi_cash_assistance

policyengine_us/parameters/gov/usda/snap/income/sources/unearned.yaml

@@ -45,6 +45,7 @@ values:
     - mi_ssp_person
     - mn_msa_person
     - mo_ssp
+    - mt_ssp
     - nc_sa
     - ne_aabd
     - nj_ssp

policyengine_us/programs.yaml

@@ -1148,6 +1148,18 @@ programs:
         verified_years: '2026'
         notes: Models 2026 basic and enhanced facility and in-home payments, including lower contracted
           rates and first-month proration. Open/shut and discharge payments are not modeled.
+      - state: MT
+        status: partial
+        name: Montana SSP
+        full_name: Montana State Supplementary Payment
+        variable: mt_ssp
+        parameter_prefix: gov.states.mt.dphhs.ssp
+        verified_years: "2026"
+        notes: >-
+          Models 2026 Montana optional supplements for state-certified
+          personal care, group home, foster care and transitional living
+          placements. Mandatory grandfathered supplementation and out-of-state
+          custody placements are not modeled.
 
   - id: social_security
     name: Social Security

policyengine_us/tests/policy/baseline/gov/states/mt/dphhs/ssp/integration.yaml

@@ -0,0 +1,214 @@
+- name: Case 1, joint payment.
+  period: 2026-01
+  absolute_error_margin: 0.01
+  input:
+    people:
+      person1:
+        age: 65
+        mt_ssp_payment_category: ASSISTED_LIVING_OR_GROUP_OR_COMMUNITY_HOME
+      person2:
+        age: 65
+        mt_ssp_payment_category: ASSISTED_LIVING_OR_GROUP_OR_COMMUNITY_HOME
+    marital_units:
+      couple:
+        members: [person1, person2]
+    tax_units:
+      unit:
+        members: [person1, person2]
+    households:
+      household:
+        members: [person1, person2]
+        state_code: MT
+  output:
+    mt_ssp: [96.5, 96.5]
+
+- name: Case 2, mixed certified settings share the joint payment.
+  period: 2026-01
+  absolute_error_margin: 0.01
+  input:
+    people:
+      person1:
+        age: 65
+        mt_ssp_payment_category: ASSISTED_LIVING_OR_GROUP_OR_COMMUNITY_HOME
+      person2:
+        age: 65
+        mt_ssp_payment_category: FOSTER_CARE
+    marital_units:
+      couple:
+        members: [person1, person2]
+    tax_units:
+      unit:
+        members: [person1, person2]
+    households:
+      household:
+        members: [person1, person2]
+        state_code: MT
+  output:
+    mt_ssp: [75.88, 75.88]
+
+- name: Case 3, joint income reduces the supplement after federal SSI.
+  period: 2026-01
+  absolute_error_margin: 0.01
+  input:
+    people:
+      person1:
+        age: 65
+        mt_ssp_payment_category: ASSISTED_LIVING_OR_GROUP_OR_COMMUNITY_HOME
+        social_security_retirement: 19_200
+      person2:
+        age: 65
+        mt_ssp_payment_category: ASSISTED_LIVING_OR_GROUP_OR_COMMUNITY_HOME
+    marital_units:
+      couple:
+        members: [person1, person2]
+    tax_units:
+      unit:
+        members: [person1, person2]
+    households:
+      household:
+        members: [person1, person2]
+        state_code: MT
+  output:
+    mt_ssp: [52, 52]
+
+- name: Case 4, ineligible spouse deeming capped at individual rate.
+  period: 2026-01
+  absolute_error_margin: 0.01
+  input:
+    people:
+      person1:
+        age: 65
+        mt_ssp_payment_category: ASSISTED_LIVING_OR_GROUP_OR_COMMUNITY_HOME
+      person2:
+        age: 40
+        mt_ssp_payment_category: NONE
+        social_security_retirement: 19_200
+    marital_units:
+      couple:
+        members: [person1, person2]
+    tax_units:
+      unit:
+        members: [person1, person2]
+    households:
+      household:
+        members: [person1, person2]
+        state_code: MT
+  output:
+    mt_ssp: [94, 0]
+
+- name: Case 5, ineligible spouse income reduces state payment.
+  period: 2026-01
+  absolute_error_margin: 0.01
+  input:
+    people:
+      person1:
+        age: 65
+        mt_ssp_payment_category: ASSISTED_LIVING_OR_GROUP_OR_COMMUNITY_HOME
+      person2:
+        age: 40
+        mt_ssp_payment_category: NONE
+        social_security_retirement: 20_400
+    marital_units:
+      couple:
+        members: [person1, person2]
+    tax_units:
+      unit:
+        members: [person1, person2]
+    households:
+      household:
+        members: [person1, person2]
+        state_code: MT
+  output:
+    mt_ssp: [4, 0]
+
+- name: Case 6, ineligible spouse combined cutoff.
+  period: 2026-01
+  absolute_error_margin: 0.01
+  input:
+    people:
+      person1:
+        age: 65
+        mt_ssp_payment_category: ASSISTED_LIVING_OR_GROUP_OR_COMMUNITY_HOME
+      person2:
+        age: 40
+        mt_ssp_payment_category: NONE
+        social_security_retirement: 20_448
+    marital_units:
+      couple:
+        members: [person1, person2]
+    tax_units:
+      unit:
+        members: [person1, person2]
+    households:
+      household:
+        members: [person1, person2]
+        state_code: MT
+  output:
+    mt_ssp: [0, 0]
+
+- name: Case 7, annual benefit in the benefit and income aggregates.
+  period: 2026
+  absolute_error_margin: 0.01
+  input:
+    state_code: MT
+    age: 65
+    mt_ssp_payment_category: ASSISTED_LIVING_OR_GROUP_OR_COMMUNITY_HOME
+    # Keeps projected SNAP out of spm_unit_benefits.
+    takes_up_snap_if_eligible: false
+  output:
+    # 94 x 12 = 1,128 Montana; 994 x 12 = 11,928 federal SSI.
+    mt_ssp: 1_128
+    household_state_benefits: 1_128
+    # 11,928 + 1,128 = 13,056.
+    spm_unit_benefits: 13_056
+    snap_unearned_income: 13_056
+    hud_unearned_income: 13_056
+
+- name: Case 8, spouses in separate marital units after one enters a certified home.
+  period: 2026-01
+  absolute_error_margin: 0.01
+  input:
+    people:
+      person1:
+        age: 65
+        mt_ssp_payment_category: ASSISTED_LIVING_OR_GROUP_OR_COMMUNITY_HOME
+      person2:
+        age: 65
+    # From the month after they stop living together, SSA treats the spouses
+    # as individuals (20 CFR 416.1801(c); SI 00501.154).
+    marital_units:
+      person1_marital_unit:
+        members: [person1]
+      person2_marital_unit:
+        members: [person2]
+    tax_units:
+      unit:
+        members: [person1, person2]
+    households:
+      household:
+        members: [person1, person2]
+        state_code: MT
+  output:
+    ssi_countable_income: [0, 0]
+    # Each spouse receives the 994 individual federal benefit rate.
+    ssi_amount_if_eligible: [994, 994]
+    ssi: [994, 994]
+    # person1: the 94 individual personal care, group or community home level.
+    # person2: no certified placement (POMS SI 01415.058 H.1 code Z), so 0.
+    mt_ssp: [94, 0]
+
+- name: Case 9, elderly homeowner or renter credit income counts the supplement.
+  period: 2026
+  absolute_error_margin: 0.01
+  input:
+    state_code: MT
+    age: 65
+    mt_ssp_payment_category: ASSISTED_LIVING_OR_GROUP_OR_COMMUNITY_HOME
+  output:
+    # 994 x 12 = 11,928 federal SSI.
+    ssi: 11_928
+    # 94 x 12 = 1,128 Montana supplement.
+    mt_ssp: 1_128
+    # MCA 15-30-2337(9)(a)(vi) counts cash public assistance and relief:
+    # 11,928 + 1,128 = 13,056.
+    mt_elderly_homeowner_or_renter_credit_gross_household_income: 13_056