MaxGhenis · Oct 21, 2026 · Oct 21, 2026
diff --git a/changelog.d/statute-bugs-mt-disability-ehrc-elderly.fixed.md b/changelog.d/statute-bugs-mt-disability-ehrc-elderly.fixed.md
@@ -0,0 +1 @@
+End Montana's disability income exclusion with its 2024 repeal, count only the federal refundable credits a household actually received in the elderly homeowner/renter credit's gross household income, and require that credit's claimant to meet the six-month owner, renter or lessee occupancy and nine-month residence tests (MCA 15-30-2338(1)(b)-(c)).
diff --git a/...ov/states/mt/tax/income/credits/elderly_homeowner_or_renter/minimum_occupancy_months.yaml b/...ov/states/mt/tax/income/credits/elderly_homeowner_or_renter/minimum_occupancy_months.yaml
@@ -0,0 +1,14 @@
+description: Montana requires a claimant of the elderly homeowner or renter credit to occupy one or more Montana dwellings as an owner, renter, or lessee for at least this many months of the claim period.
+values:
+  2009-01-01: 6
+metadata:
+  unit: month
+  period: year
+  label: Montana elderly homeowner or renter credit minimum qualifying occupancy months
+  reference:
+    - title: MCA 15-30-2338(1)(c)
+      href: https://mca.legmt.gov/bills/mca/title_0150/chapter_0300/part_0230/section_0380/0150-0300-0230-0380.html
+    - title: MCA 15-30-2338(1)(c) (2009)
+      href: https://mca.legmt.gov/bills/2009/mca/15/30/15-30-2338.htm
+    - title: 2025 Montana Form 2 instructions, Elderly Homeowner/Renter Credit, "You occupied a Montana residence as a renter, owner, or lessee for at least six months during the tax year"
+      href: https://revenue.mt.gov/files/forms/Montana-Individual-Income-Tax-Return-Form-2-Instructions/2025_Montana_Individual_Income_Tax_Return_Form_2_Instructions.pdf#page=44
diff --git a/...ov/states/mt/tax/income/credits/elderly_homeowner_or_renter/minimum_residency_months.yaml b/...ov/states/mt/tax/income/credits/elderly_homeowner_or_renter/minimum_residency_months.yaml
@@ -0,0 +1,14 @@
+description: Montana requires a claimant of the elderly homeowner or renter credit to reside in Montana for at least this many months of the claim period.
+values:
+  2009-01-01: 9
+metadata:
+  unit: month
+  period: year
+  label: Montana elderly homeowner or renter credit minimum residency months
+  reference:
+    - title: MCA 15-30-2338(1)(b)
+      href: https://mca.legmt.gov/bills/mca/title_0150/chapter_0300/part_0230/section_0380/0150-0300-0230-0380.html
+    - title: MCA 15-30-2338(1)(b) (2009)
+      href: https://mca.legmt.gov/bills/2009/mca/15/30/15-30-2338.htm
+    - title: 2025 Montana Form 2 instructions, Elderly Homeowner/Renter Credit, "You lived in Montana for at least nine months during the tax year"
+      href: https://revenue.mt.gov/files/forms/Montana-Individual-Income-Tax-Return-Form-2-Instructions/2025_Montana_Individual_Income_Tax_Return_Form_2_Instructions.pdf#page=44
diff --git a/policyengine_us/parameters/gov/states/mt/tax/income/subtractions/subtractions.yaml b/policyengine_us/parameters/gov/states/mt/tax/income/subtractions/subtractions.yaml
@@ -19,7 +19,9 @@ values:
     - mt_interest_exemption_person
     - mt_tuition_subtraction_person
     - mt_old_age_subtraction
-    - mt_disability_income_exclusion_person
+    # 2021 Mont. Laws ch. 503 (SB 399) section 65 repealed 15-30-2110, MCA,
+    # and with it the disability income exclusion, for tax years beginning
+    # after December 31, 2023 (section 70(1)).
     - salt_refund_income # MCA 15-30-2120 / Form 2 Subtractions Schedule
   2025-01-01:
     # Section 15-30-2120 starts from federal taxable income, so federal
@@ -29,7 +31,6 @@ values:
     - mt_interest_exemption_person
     - mt_tuition_subtraction_person
     - mt_old_age_subtraction
-    - mt_disability_income_exclusion_person
     # TODO: Remove this subtraction starting in 2029 because the federal
     # Schedule 1-A deductions expire after 2028.
     - mt_federal_obbba_subtraction
@@ -49,3 +50,7 @@ metadata:
       href: https://leg.mt.gov/bills/mca/title_0150/chapter_0300/part_0210/section_0100/0150-0300-0210-0100.html
     - title: 2025 Montana Form 2 Instructions
       href: https://revenuefiles.mt.gov/files/Forms/Montana-Individual-Income-Tax-Return-Form-2-Instructions/2025_Montana_Individual_Income_Tax_Return_Form_2_Instructions.pdf#page=21
+    - title: "2021 Montana Session Laws, chapter 503 (SB 399), section 65 (repealer) and section 70 (effective dates) #page 68,70"
+      href: https://archive.legmt.gov/content/Publications/sales/2021SessionLaws_V3_ERRATA-VERSION.pdf#page=68
+    - title: 2024 Montana Form 2 instructions, repealed deductions
+      href: https://revenue.mt.gov/files/forms/Montana-Individual-Income-Tax-Return-Form-2-Instructions/2024_Montana_Individual_Income_Tax_Return_Form_2_Instructions.pdf#page=5
diff --git a/...tax/income/credits/elderly_homeowner_or_renter/mt_elderly_homeowner_or_renter_credit.yaml b/...tax/income/credits/elderly_homeowner_or_renter/mt_elderly_homeowner_or_renter_credit.yaml
@@ -216,6 +216,8 @@
         age: 63
         employment_income: 20_892.60
         real_estate_taxes: 863.08
+        # The third Economic Impact Payment, received during 2021.
+        mt_elderly_homeowner_or_renter_credit_federal_refundable_credits: 1_400
     tax_units:
       tax_unit:
         members: [person1]
@@ -227,13 +229,14 @@
     # (863.08 - (gross_hh - 6,300) x 0.05) x 1.0, capped at $1,000.
     # 2021 instructions, line 7: "Refundable credits include the federal and
     # Montana Earned Income Tax Credit, the federal Child Tax Credits,
-    # Economic Impact Payments". Federal EITC (ARPA, no qualifying child)
-    # 1_502 - 15.3% x (20_892.60 - 11_610) = 81.76; Montana EITC 3% = 2.45;
-    # Economic Impact Payment 1_400. Line 10 = 20_892.60 + 1_484.21 =
-    # 22_376.81; line 12 = 16_076.81; line 14 = 803.84; line 19 = 863.08 -
-    # 803.84 = 59.24. The earlier expected value, 133.33, counted only the
-    # Montana EITC.
-    mt_elderly_homeowner_or_renter_credit: 59.24
+    # Economic Impact Payments". Received in 2021: the 1_400 Economic Impact
+    # Payment. The 2021 federal EITC (ARPA, no qualifying child), 1_502 -
+    # 15.3% x (20_892.60 - 11_610) = 81.76, is paid in 2022, so it is not;
+    # the Montana EITC on the 2021 return, 3% = 2.45, counts as the model's
+    # Montana refundable credits. Line 10 = 20_892.60 + 1_400 + 2.45 =
+    # 22_295.05; line 12 = 15_995.05; line 14 = 799.75; line 19 = 863.08 -
+    # 799.75 = 63.33.
+    mt_elderly_homeowner_or_renter_credit: 63.33
 
 - name: MT EHRC uses the $12,600 exclusion from 2022 (HB 191)
   period: 2022
@@ -937,6 +940,8 @@
       person2:
         age: 40
         employment_income: 10_000
+        # Federal EITC refund received during 2024.
+        mt_elderly_homeowner_or_renter_credit_federal_refundable_credits: 632
     tax_units:
       tax_unit1:
         members: [person1]
@@ -949,9 +954,9 @@
   output:
     # The claimant's adult son lives in the household and files his own
     # return. Line 5 pensions 20_000. Line 8, refundable credits received by
-    # all household members: his federal EITC 632 (Rev. Proc. 2023-34, no
-    # qualifying child, wages between 8_260 and 10_330) and Montana EITC
-    # 10% x 632 = 63.20, 695.20 in all. Line 17 his wages 10_000. Line 18
+    # all household members: the 632 federal EITC refund he received in 2024
+    # and Montana EITC 10% x 632 = 63.20 (Rev. Proc. 2023-34, no qualifying
+    # child, wages between 8_260 and 10_330), 695.20 in all. Line 17 his wages 10_000. Line 18
     # gross household income 30_695.20; line 20 = 30_695.20 - 12_600 =
     # 18_095.20; line 21 = 0.05; line 22 = 904.76; line 27 = 2_000 - 904.76
     # = 1_095.24; line 28 = 1_095.24 (under 1_150); line 29 = 100%; line 30 =
@@ -971,6 +976,8 @@
       person2:
         age: 30
         employment_income: 10_000
+        # Federal EITC and refundable CTC received during 2024.
+        mt_elderly_homeowner_or_renter_credit_federal_refundable_credits: 4_525
       person3:
         age: 5
     tax_units:
@@ -984,8 +991,9 @@
         state_name: MT
   output:
     # The claimant's daughter and grandchild live in the household; the
-    # daughter files her own return. Line 8: federal EITC 34% x 10_000 =
-    # 3_400, refundable part of the federal child tax credit
+    # daughter files her own return. Line 8, received during 2024: federal
+    # EITC 34% x 10_000 = 3_400, refundable part of the federal child tax
+    # credit
     # min(1_700, 15% x (10_000 - 2_500)) = 1_125, Montana EITC 340; 4_865 in
     # all. Line 17 her wages 10_000. Line 18 = 20_000 + 4_865 + 10_000 =
     # 34_865; line 20 = 22_265; line 22 = 22_265 x 0.05 = 1_113.25; line 27 =
@@ -1007,6 +1015,8 @@
       person2:
         age: 30
         employment_income: 12_000
+        # Federal EITC and refundable CTC received during 2024.
+        mt_elderly_homeowner_or_renter_credit_federal_refundable_credits: 5_505
       person3:
         age: 5
     tax_units:
@@ -1019,7 +1029,7 @@
         members: [person1, person2, person3]
         state_name: MT
   output:
-    # Line 8: federal EITC 34% x 12_000 = 4_080 (under the 12_390 earned
+    # Line 8, received during 2024: federal EITC 34% x 12_000 = 4_080 (under the 12_390 earned
     # income amount), refundable child tax credit
     # min(1_700, 15% x 9_500) = 1_425, Montana EITC 408; 5_913 in all.
     # Line 18 = 20_000 + 5_913 + 12_000 = 37_913; line 20 = 25_313;
@@ -1075,6 +1085,8 @@
       person2:
         age: 40
         employment_income: 10_000
+        # Federal EITC refund received during 2023.
+        mt_elderly_homeowner_or_renter_credit_federal_refundable_credits: 584.70
     tax_units:
       tax_unit1:
         members: [person1]
@@ -1109,26 +1121,26 @@
         rent: 4_800
         mt_elderly_homeowner_or_renter_credit_received: 60
         mt_elderly_homeowner_or_renter_credit_property_tax_rebate_received: 20
+        mt_elderly_homeowner_or_renter_credit_federal_refundable_credits: 500
       person2:
         age: 70
         taxable_pension_income: 15_000
         rent: 7_200
         mt_elderly_homeowner_or_renter_credit_received: 40
         mt_elderly_homeowner_or_renter_credit_property_tax_rebate_received: 80
+        mt_elderly_homeowner_or_renter_credit_federal_refundable_credits: 300
     tax_units:
       tax_unit1:
         members: [person1]
-        income_tax_refundable_credits: 500
       tax_unit2:
         members: [person2]
-        income_tax_refundable_credits: 300
     households:
       household:
         members: [person1, person2]
         state_code: MT
   output:
-    # Schedule 2EC line 8 counts each return's federal refundable credits
-    # once, plus actual elderly-credit and rebate receipts. Person amounts:
+    # Schedule 2EC line 8 counts the federal refundable credits each person
+    # received, plus actual elderly-credit and rebate receipts. Person amounts:
     # 10_000 + 500 + 60 + 20 = 10_580; 15_000 + 300 + 40 + 80 = 15_420.
     # Line 18 = 26_000; line 22 = (26_000 - 12_600) * .05 = 670.
     # Line 25 rent equivalents = [4_800, 7_200] * .15 = [720, 1_080].
@@ -1297,7 +1309,7 @@
     # Line 18 = 20_000 + 10_000 = 30_000; line 22 = 870; line 30 = 1_130.
     mt_elderly_homeowner_or_renter_credit: [1_130, 0]
 
-- name: 2024 Schedule 2EC, a parent living in an adult child's home claims the child's property tax as rent
+- name: 2024 Schedule 2EC, a parent without owner, renter or lessee status in an adult child's home cannot claim
   period: 2024
   absolute_error_margin: 0.01
   input:
@@ -1327,6 +1339,51 @@
       household:
         members: [person1, person2]
         state_name: MT
+  output:
+    # MCA 15-30-2338(1)(c): a claimant "must have occupied one or more
+    # dwellings in Montana as an owner, renter, or lessee for at least 6
+    # months". The parent pays no rent and is billed no property tax, and
+    # the child's bill does not establish the parent's status. ARM
+    # 42.4.302(2)(b) lets only an eligible claimant use another's bill as
+    # rent. The child is 45 (§ 15-30-2338(1)(a)). Neither may claim; before
+    # this test the parent's credit was 341.
+    mt_elderly_homeowner_or_renter_credit_eligible: [false, false]
+    mt_elderly_homeowner_or_renter_credit: [0, 0]
+    mt_refundable_credits: [0, 0]
+
+- name: 2024 Schedule 2EC, a parent who leases an adult child's home rent-free claims the child's property tax as rent
+  period: 2024
+  absolute_error_margin: 0.01
+  input:
+    people:
+      person1:
+        age: 80
+        taxable_pension_income: 14_000
+        rent: 0
+        ssi: 0
+        # A documented lessee for the whole year.
+        mt_elderly_homeowner_or_renter_credit_qualifying_occupancy_months: 12
+      person2:
+        age: 45
+        taxable_interest_income: 6_000
+        rent: 0
+        real_estate_taxes: 4_000
+        ssi: 0
+        mt_elderly_homeowner_or_renter_credit_qualifying_occupancy_months: 12
+    tax_units:
+      tax_unit1:
+        members: [person1]
+      tax_unit2:
+        members: [person2]
+    marital_units:
+      marital_unit1:
+        members: [person1]
+      marital_unit2:
+        members: [person2]
+    households:
+      household:
+        members: [person1, person2]
+        state_name: MT
   output:
     # The home is in the child's name. "If the property occupied by you is
     # in a name other than your own, the property taxes billed for that
@@ -1336,8 +1393,7 @@
     # line 21 = 0.035; line 22 = 259.
     # Parent: line 23 = 0; line 24 = 4_000 (the child's bill, as rent);
     # line 25 = 600; line 26 = 600; line 27 = 600 - 259 = 341; line 28 =
-    # 341; line 29 = 100% (under 35_000); line 30 = 341. Before this rule
-    # the parent's line 24 was 0 and the credit 0.
+    # 341; line 29 = 100% (under 35_000); line 30 = 341.
     # The child is 45, so not a claimant (§ 15-30-2338(1)(a)).
     mt_elderly_homeowner_or_renter_credit_net_household_income: [259, 0]
     mt_elderly_homeowner_or_renter_credit_gross_rent: [4_000, 0]
@@ -1453,12 +1509,15 @@
   output:
     # SSI is pinned at 0 to isolate the credit's arithmetic. Line 18 =
     # 20_000; line 20 = 7_400; line 21 = 0.035; line 22 = 259.
-    # person1 (home in person2's name): line 24 = 2_000; line 25 = 300;
-    # line 27 = 300 - 259 = 41.
+    # person1 pays no rent and is billed nothing, so nothing shows that they
+    # occupy the home as an owner, renter or lessee (MCA 15-30-2338(1)(c)):
+    # not eligible. As a lessee they would have line 24 = 2_000, line 25 =
+    # 300 and line 27 = 300 - 259 = 41.
     # person2: line 23 = 2_000; line 27 = 2_000 - 259 = 1_741; line 28 =
     # 1_150 cap.
     # One claimant per household (§ 15-30-2341(1)): person2 claims 1_150.
-    mt_elderly_homeowner_or_renter_credit_pre_one_claimant: [41, 1_150]
+    mt_elderly_homeowner_or_renter_credit_eligible: [false, true]
+    mt_elderly_homeowner_or_renter_credit_pre_one_claimant: [0, 1_150]
     mt_elderly_homeowner_or_renter_credit_selected_claimant: [false, true]
     mt_elderly_homeowner_or_renter_credit: [0, 1_150]
 
@@ -1585,15 +1644,20 @@
         taxable_pension_income: 14_000
         rent: 0
         ssi: 0
+        # A rent-free lessee. An input for one person gives the others the
+        # input default, not the formula, so record everyone's months.
+        mt_elderly_homeowner_or_renter_credit_qualifying_occupancy_months: 12
       person2:
         age: 45
         rent: 0
         ssi: 0
+        mt_elderly_homeowner_or_renter_credit_qualifying_occupancy_months: 12
       person3:
         age: 43
         rent: 0
         real_estate_taxes: 4_000
         ssi: 0
+        mt_elderly_homeowner_or_renter_credit_qualifying_occupancy_months: 12
     tax_units:
       tax_unit1:
         members: [person1]

diff --git a/...omeowner_or_renter/mt_elderly_homeowner_or_renter_credit_disability_and_unemployment.yaml b/...omeowner_or_renter/mt_elderly_homeowner_or_renter_credit_disability_and_unemployment.yaml
@@ -188,6 +188,8 @@
         unemployment_compensation: 9_000
         real_estate_taxes: 1_500
         ssi: 0
+        # Economic Impact Payments received during 2020.
+        mt_elderly_homeowner_or_renter_credit_federal_refundable_credits: 1_800
     tax_units:
       tax_unit:
         members: [person1]
@@ -198,7 +200,8 @@
   output:
     # IRC 85(c) excludes the 9_000 from 2020 federal AGI (AGI without it is
     # 16_000, under 150_000). Line 1 federal AGI 16_000; line 7 refundable
-    # credits received, the 2020 recovery rebate credit 1_200 + 600 = 1_800;
+    # credits received, the 2020 Economic Impact Payments 1_200 + 600 =
+    # 1_800;
     # line 8 other income not listed above, the excluded 9_000; line 10 =
     # 26_800.
     adjusted_gross_income_person: 16_000
@@ -221,10 +224,13 @@
         taxable_pension_income: 14_000
         rent: 12_000
         ssi: 0
+        # Economic Impact Payments received during 2020.
+        mt_elderly_homeowner_or_renter_credit_federal_refundable_credits: 1_800
       person2:
         age: 40
         unemployment_compensation: 14_000
         ssi: 0
+        mt_elderly_homeowner_or_renter_credit_federal_refundable_credits: 1_800
     tax_units:
       tax_unit1:
         members: [person1]
@@ -237,8 +243,8 @@
   output:
     # The claimant's daughter files her own return. Of her 14_000, 10_200 is
     # excluded and 14_000 - 10_200 = 3_800 is in her federal AGI. Line 1
-    # federal AGI 14_000 + 3_800 = 17_800; line 7 each return's 2020
-    # recovery rebate credit, 1_800 + 1_800 = 3_600; line 8 her excluded
+    # federal AGI 14_000 + 3_800 = 17_800; line 7 the 2020 Economic Impact
+    # Payments each received, 1_800 + 1_800 = 3_600; line 8 her excluded
     # 10_200; line 10 = 31_600.
     adjusted_gross_income_person: [14_000, 3_800]
     mt_elderly_homeowner_or_renter_credit_gross_household_income: [15_800, 15_800]
@@ -260,6 +266,8 @@
         taxable_pension_income: 15_000
         real_estate_taxes: 1_400
         ssi: 0
+        # Economic Impact Payments received during 2020.
+        mt_elderly_homeowner_or_renter_credit_federal_refundable_credits: 1_800
       person2:
         age: 20
         is_full_time_student: true
@@ -277,7 +285,7 @@
     # The claimant's grandson, a student, is her dependent. All of his 4_000
     # is excluded from federal AGI, and his own gross income counts it in
     # full, so nothing more is added for it. Line 1 federal AGI 15_000; line
-    # 7 the recovery rebate credit 1_800; line 8 his 4_000; line 10 = 20_800.
+    # 7 the Economic Impact Payments received, 1_800; line 8 his 4_000; line 10 = 20_800.
     mt_elderly_homeowner_or_renter_credit_unemployment_compensation_addback: [0, 0]
     mt_elderly_homeowner_or_renter_credit_gross_household_income: [16_800, 4_000]
     # Line 12 = 14_500; line 13 = 0.05; line 14 = 725.
@@ -296,6 +304,8 @@
         unemployment_compensation: 9_000
         real_estate_taxes: 1_500
         ssi: 0
+        # Economic Impact Payment received during 2021.
+        mt_elderly_homeowner_or_renter_credit_federal_refundable_credits: 1_400
     tax_units:
       tax_unit:
         members: [person1]
@@ -305,7 +315,7 @@
         state_name: MT
   output:
     # No exclusion in 2021. Line 1 federal AGI 25_000; line 7 the 2021
-    # recovery rebate credit 1_400; line 10 = 26_400.
+    # Economic Impact Payment received, 1_400; line 10 = 26_400.
     mt_elderly_homeowner_or_renter_credit_unemployment_compensation_addback: 0
     mt_elderly_homeowner_or_renter_credit_gross_household_income: 26_400
     # Line 12 = 20_100; line 13 = 0.05; line 14 = 1_005.
Original file line number	Diff line number	Diff line change
		@@ -0,0 +1 @@
		End Montana's disability income exclusion with its 2024 repeal, count only the federal refundable credits a household actually received in the elderly homeowner/renter credit's gross household income, and require that credit's claimant to meet the six-month owner, renter or lessee occupancy and nine-month residence tests (MCA 15-30-2338(1)(b)-(c)).