diff --git a/changelog.d/mi-ssp.added.md b/changelog.d/mi-ssp.added.md
new file mode 100644
index 00000000000..34b602db9f5
--- /dev/null
+++ b/changelog.d/mi-ssp.added.md
@@ -0,0 +1 @@
+Added Michigan State Supplementary Payment (SSP) program.
diff --git a/policyengine_us/parameters/gov/household/household_state_benefits.yaml b/policyengine_us/parameters/gov/household/household_state_benefits.yaml
index 619bf682302..9d3249a8127 100644
--- a/policyengine_us/parameters/gov/household/household_state_benefits.yaml
+++ b/policyengine_us/parameters/gov/household/household_state_benefits.yaml
@@ -12,6 +12,8 @@ values:
     - ga_ssp
     # Massachusetts benefits
     - ma_state_supplement
+    # Michigan benefits
+    - mi_ssp
     # Colorado benefits
     - co_state_supplement
     - co_oap
@@ -67,6 +69,8 @@ values:
     - ga_ssp
     # Massachusetts benefits
     - ma_state_supplement
+    # Michigan benefits
+    - mi_ssp
     # Colorado benefits
     - co_state_supplement
     - co_oap
diff --git a/policyengine_us/parameters/gov/states/mi/mdhhs/ssp/payment/couple.yaml b/policyengine_us/parameters/gov/states/mi/mdhhs/ssp/payment/couple.yaml
new file mode 100644
index 00000000000..fafbaddee14
--- /dev/null
+++ b/policyengine_us/parameters/gov/states/mi/mdhhs/ssp/payment/couple.yaml
@@ -0,0 +1,55 @@
+description: Michigan provides this amount as the monthly couple payment standard under the State Supplementary Payment program.
+
+metadata:
+  unit: currency-USD
+  period: month
+  label: Michigan SSP couple payment
+  breakdown:
+    - mi_ssp_payment_category
+  reference:
+    - title: MDHHS RFT 248, SSI Payment Levels
+      href: https://mdhhs-pres-prod.michigan.gov/olmweb/ex/RF/Public/RFT/248.pdf#page=2
+    - title: MDHHS BEM 660, State SSI Payment, Legal Base
+      href: https://mdhhs-pres-prod.michigan.gov/olmweb/EX/BP/Public/BEM/660.pdf#page=4
+    - title: MCL 400.10, Social Welfare Act, supplementary payments
+      href: https://www.legislature.mi.gov/Laws/MCL?objectName=mcl-400-10
+    - title: SSA 2011 State Assistance Programs, Michigan baseline
+      href: https://www.ssa.gov/policy/docs/progdesc/ssi_st_asst/2011/mi.html
+    - title: MDHHS RFT 248, SSI Payment Levels (RFB 2016-001 archive)
+      href: https://web.archive.org/web/20161223122049id_/https://dhhs.michigan.gov/OLMWEB/EX/RF/Public/RFT/248.pdf#page=2
+    - title: MDHHS RFT 248, SSI Payment Levels (RFB 2020-001 archive)
+      href: https://web.archive.org/web/20200923083110id_/https://dhhs.michigan.gov/OLMWEB/EX/RF/Public/RFT/248.pdf#page=2
+    - title: MDHHS RFT 248, SSI Payment Levels (RFB 2022-002 archive)
+      href: https://web.archive.org/web/20220309172236id_/https://dhhs.michigan.gov/OLMWEB/EX/RF/Public/RFT/248.pdf#page=2
+    - title: MDHHS RFT 248, SSI Payment Levels (RFB 2024-001 archive)
+      href: https://web.archive.org/web/20240112012718id_/https://dhhs.michigan.gov/OLMWEB/EX/RF/Public/RFT/248.pdf#page=2
+
+# Couple rates start at 2016-01-01. SSA 2011 baseline shows MI couple
+# rates were restructured between 2011 and 2016 (e.g. IL couple was $28
+# in 2011, $21 from 2016 onward); pre-2016 history is not modeled.
+INDEPENDENT_LIVING:
+  2016-01-01: 21
+HOUSEHOLD_OF_ANOTHER:
+  2016-01-01: 13.96
+DOMICILIARY_CARE:
+  2016-01-01: 540
+  2020-01-01: 565
+  2022-01-01: 595
+  2024-01-01: 645
+  2026-01-01: 671
+PERSONAL_CARE:
+  2016-01-01: 681
+  2020-01-01: 706
+  2022-01-01: 736
+  2024-01-01: 786
+  2026-01-01: 812
+HOME_FOR_AGED:
+  2016-01-01: 724.6
+  2020-01-01: 749.6
+  2022-01-01: 779.6
+  2024-01-01: 829.6
+  2026-01-01: 855.6
+INSTITUTION:
+  2016-01-01: 14
+NONE:
+  2016-01-01: 0
diff --git a/policyengine_us/parameters/gov/states/mi/mdhhs/ssp/payment/individual.yaml b/policyengine_us/parameters/gov/states/mi/mdhhs/ssp/payment/individual.yaml
new file mode 100644
index 00000000000..a25db30bcfc
--- /dev/null
+++ b/policyengine_us/parameters/gov/states/mi/mdhhs/ssp/payment/individual.yaml
@@ -0,0 +1,36 @@
+description: Michigan provides this amount as the monthly individual payment standard under the State Supplementary Payment program.
+
+metadata:
+  unit: currency-USD
+  period: month
+  label: Michigan SSP individual payment
+  breakdown:
+    - mi_ssp_payment_category
+  reference:
+    - title: MDHHS RFT 248, SSI Payment Levels
+      href: https://mdhhs-pres-prod.michigan.gov/olmweb/ex/RF/Public/RFT/248.pdf#page=2
+    - title: MDHHS BEM 660, State SSI Payment, Legal Base
+      href: https://mdhhs-pres-prod.michigan.gov/olmweb/EX/BP/Public/BEM/660.pdf#page=4
+    - title: MCL 400.10, Social Welfare Act, supplementary payments
+      href: https://www.legislature.mi.gov/Laws/MCL?objectName=mcl-400-10
+    - title: SSA State Assistance Programs for SSI Recipients, Michigan, Table 1
+      href: https://www.ssa.gov/policy/docs/progdesc/ssi_st_asst/2011/mi.html
+    - title: MDHHS RFT 248, SSI Payment Levels (RFB 2016-001 archive)
+      href: https://web.archive.org/web/20161223122049id_/https://dhhs.michigan.gov/OLMWEB/EX/RF/Public/RFT/248.pdf#page=2
+
+# Individual rates have not changed since 2016 across all six living
+# arrangements (verified against RFT 248 RFB 2016-001 through RFB 2026-001).
+INDEPENDENT_LIVING:
+  2016-01-01: 14
+HOUSEHOLD_OF_ANOTHER:
+  2016-01-01: 9.33
+DOMICILIARY_CARE:
+  2016-01-01: 87
+PERSONAL_CARE:
+  2016-01-01: 157.5
+HOME_FOR_AGED:
+  2016-01-01: 179.3
+INSTITUTION:
+  2016-01-01: 7
+NONE:
+  2016-01-01: 0
diff --git a/policyengine_us/programs.yaml b/policyengine_us/programs.yaml
index 801129254f1..5ecc1850a8d 100644
--- a/policyengine_us/programs.yaml
+++ b/policyengine_us/programs.yaml
@@ -651,6 +651,12 @@ programs:
         name: Massachusetts SSP
         full_name: Massachusetts State Supplementary Payment
         variable: ma_state_supplement
+      - state: MI
+        status: complete
+        name: Michigan SSP
+        full_name: Michigan State Supplementary Payment
+        variable: mi_ssp
+        parameter_prefix: gov.states.mi.mdhhs.ssp
       - state: KS
         status: complete
         name: Kansas SSPP
diff --git a/policyengine_us/tests/policy/baseline/gov/states/mi/mdhhs/ssp/integration.yaml b/policyengine_us/tests/policy/baseline/gov/states/mi/mdhhs/ssp/integration.yaml
new file mode 100644
index 00000000000..f639e388e1e
--- /dev/null
+++ b/policyengine_us/tests/policy/baseline/gov/states/mi/mdhhs/ssp/integration.yaml
@@ -0,0 +1,839 @@
+- name: Case 1, single eligible person in Independent Living gets $14.
+  absolute_error_margin: 0.01
+  period: 2024-01
+  input:
+    people:
+      person1:
+        is_ssi_eligible: true
+        mi_ssp_living_arrangement: INDEPENDENT_LIVING
+    spm_units:
+      spm_unit:
+        members: [person1]
+    households:
+      household:
+        members: [person1]
+        state_code: MI
+  output:
+    # Single eligible person, IL → individual rate $14/mo
+    mi_ssp_eligible: true
+    mi_ssp_person: 14
+    mi_ssp: 14
+
+- name: Case 2, single eligible person in Personal Care gets $157.50.
+  absolute_error_margin: 0.01
+  period: 2024-01
+  input:
+    people:
+      person1:
+        is_ssi_eligible: true
+        mi_ssp_living_arrangement: PERSONAL_CARE
+    spm_units:
+      spm_unit:
+        members: [person1]
+    households:
+      household:
+        members: [person1]
+        state_code: MI
+  output:
+    # Single eligible person, Personal Care → individual rate $157.50/mo
+    mi_ssp_eligible: true
+    mi_ssp_person: 157.50
+    mi_ssp: 157.50
+
+- name: Case 3, single eligible person in Home for Aged gets $179.30.
+  absolute_error_margin: 0.01
+  period: 2024-01
+  input:
+    people:
+      person1:
+        is_ssi_eligible: true
+        mi_ssp_living_arrangement: HOME_FOR_AGED
+    spm_units:
+      spm_unit:
+        members: [person1]
+    households:
+      household:
+        members: [person1]
+        state_code: MI
+  output:
+    # Single eligible person, Home for Aged → individual rate $179.30/mo
+    mi_ssp_eligible: true
+    mi_ssp_person: 179.30
+    mi_ssp: 179.30
+
+- name: Case 4, joint SSI couple both in Independent Living gets $21 total.
+  absolute_error_margin: 0.01
+  period: 2024-01
+  input:
+    people:
+      person1:
+        # $707/mo SSI = $8,484/yr couple half
+        ssi: 8_484
+        is_ssi_aged_blind_disabled: true
+        is_tax_unit_head_or_spouse: true
+        mi_ssp_living_arrangement: INDEPENDENT_LIVING
+      person2:
+        # $707/mo SSI = $8,484/yr couple half
+        ssi: 8_484
+        is_ssi_aged_blind_disabled: true
+        is_tax_unit_head_or_spouse: true
+        mi_ssp_living_arrangement: INDEPENDENT_LIVING
+    marital_units:
+      marital_unit:
+        members: [person1, person2]
+    tax_units:
+      tax_unit:
+        members: [person1, person2]
+    spm_units:
+      spm_unit:
+        members: [person1, person2]
+    households:
+      household:
+        members: [person1, person2]
+        state_code: MI
+  output:
+    # Joint claim + both eligible + same LA → couple rate $21 / 2 = $10.50 each
+    mi_ssp_eligible: [true, true]
+    mi_ssp_person: [10.50, 10.50]
+    # SPM unit total = $10.50 + $10.50 = $21
+    mi_ssp: 21
+
+- name: Case 5, joint SSI couple both in Domiciliary Care 2024 gets $645 total.
+  absolute_error_margin: 0.01
+  period: 2024-01
+  input:
+    people:
+      person1:
+        # $30/mo SSI = $360/yr institutional rate
+        ssi: 360
+        is_ssi_aged_blind_disabled: true
+        is_tax_unit_head_or_spouse: true
+        mi_ssp_living_arrangement: DOMICILIARY_CARE
+      person2:
+        # $30/mo SSI = $360/yr institutional rate
+        ssi: 360
+        is_ssi_aged_blind_disabled: true
+        is_tax_unit_head_or_spouse: true
+        mi_ssp_living_arrangement: DOMICILIARY_CARE
+    marital_units:
+      marital_unit:
+        members: [person1, person2]
+    tax_units:
+      tax_unit:
+        members: [person1, person2]
+    spm_units:
+      spm_unit:
+        members: [person1, person2]
+    households:
+      household:
+        members: [person1, person2]
+        state_code: MI
+  output:
+    # 2024 Domiciliary Care couple rate $645 / 2 = $322.50 each
+    mi_ssp_eligible: [true, true]
+    mi_ssp_person: [322.50, 322.50]
+    # SPM unit total = $322.50 + $322.50 = $645
+    mi_ssp: 645
+
+- name: Case 6, joint SSI couple in mismatched arrangements falls back to individual.
+  absolute_error_margin: 0.01
+  period: 2024-01
+  input:
+    people:
+      person1:
+        # $707/mo SSI = $8,484/yr couple half
+        ssi: 8_484
+        is_ssi_aged_blind_disabled: true
+        is_tax_unit_head_or_spouse: true
+        mi_ssp_living_arrangement: INDEPENDENT_LIVING
+      person2:
+        # $707/mo SSI = $8,484/yr couple half
+        ssi: 8_484
+        is_ssi_aged_blind_disabled: true
+        is_tax_unit_head_or_spouse: true
+        mi_ssp_living_arrangement: HOUSEHOLD_OF_ANOTHER
+    marital_units:
+      marital_unit:
+        members: [person1, person2]
+    tax_units:
+      tax_unit:
+        members: [person1, person2]
+    spm_units:
+      spm_unit:
+        members: [person1, person2]
+    households:
+      household:
+        members: [person1, person2]
+        state_code: MI
+  output:
+    # Different arrangements → individual rates
+    # person1: IL individual = $14, person2: HoA individual = $9.33
+    mi_ssp_eligible: [true, true]
+    mi_ssp_person: [14, 9.33]
+    # SPM unit total = $14 + $9.33 = $23.33
+    mi_ssp: 23.33
+
+- name: Case 7, person not receiving SSI gets zero.
+  absolute_error_margin: 0.01
+  period: 2024-01
+  input:
+    people:
+      person1:
+        ssi: 0
+        mi_ssp_living_arrangement: INDEPENDENT_LIVING
+    spm_units:
+      spm_unit:
+        members: [person1]
+    households:
+      household:
+        members: [person1]
+        state_code: MI
+  output:
+    # SSI = 0 (income too high for federal SSI) → not eligible
+    mi_ssp_eligible: false
+    mi_ssp_person: 0
+    mi_ssp: 0
+
+- name: Case 8, Home for Aged couple boundary 2023 vs 2024 reflects COLA.
+  absolute_error_margin: 0.01
+  period: 2023-01
+  input:
+    people:
+      person1:
+        # $30/mo SSI = $360/yr institutional rate
+        ssi: 360
+        is_ssi_aged_blind_disabled: true
+        is_tax_unit_head_or_spouse: true
+        mi_ssp_living_arrangement: HOME_FOR_AGED
+      person2:
+        # $30/mo SSI = $360/yr institutional rate
+        ssi: 360
+        is_ssi_aged_blind_disabled: true
+        is_tax_unit_head_or_spouse: true
+        mi_ssp_living_arrangement: HOME_FOR_AGED
+    marital_units:
+      marital_unit:
+        members: [person1, person2]
+    tax_units:
+      tax_unit:
+        members: [person1, person2]
+    spm_units:
+      spm_unit:
+        members: [person1, person2]
+    households:
+      household:
+        members: [person1, person2]
+        state_code: MI
+  output:
+    # 2022-2023 Home for Aged couple rate $779.60 / 2 = $389.80 each
+    mi_ssp_eligible: [true, true]
+    mi_ssp_person: [389.80, 389.80]
+    # SPM unit total = $779.60
+    mi_ssp: 779.60
+
+- name: Case 9, family with one SSI recipient and non-SSI spouse pays only recipient.
+  absolute_error_margin: 0.01
+  period: 2024-01
+  input:
+    people:
+      person1:
+        # $943/mo SSI = $11,316/yr individual FBR
+        ssi: 11_316
+        is_ssi_aged_blind_disabled: true
+        is_tax_unit_head_or_spouse: true
+        mi_ssp_living_arrangement: INDEPENDENT_LIVING
+      person2:
+        ssi: 0
+        is_ssi_aged_blind_disabled: false
+        is_tax_unit_head_or_spouse: true
+        mi_ssp_living_arrangement: INDEPENDENT_LIVING
+    marital_units:
+      marital_unit:
+        members: [person1, person2]
+    tax_units:
+      tax_unit:
+        members: [person1, person2]
+    spm_units:
+      spm_unit:
+        members: [person1, person2]
+    households:
+      household:
+        members: [person1, person2]
+        state_code: MI
+  output:
+    # Non-SSI spouse breaks joint-claim test → person1 gets individual $14
+    mi_ssp_eligible: [true, false]
+    mi_ssp_person: [14, 0]
+    # SPM unit total = $14
+    mi_ssp: 14
+
+- name: Case 10, couple same LA but only one is SSI-eligible falls back to individual.
+  absolute_error_margin: 0.01
+  period: 2024-01
+  input:
+    people:
+      person1:
+        is_ssi_eligible: true
+        is_ssi_aged_blind_disabled: true
+        is_tax_unit_head_or_spouse: true
+        mi_ssp_living_arrangement: INDEPENDENT_LIVING
+      person2:
+        is_ssi_aged_blind_disabled: true
+        is_ssi_eligible: false
+        is_tax_unit_head_or_spouse: true
+        mi_ssp_living_arrangement: INDEPENDENT_LIVING
+    marital_units:
+      marital_unit:
+        members: [person1, person2]
+    tax_units:
+      tax_unit:
+        members: [person1, person2]
+    spm_units:
+      spm_unit:
+        members: [person1, person2]
+    households:
+      household:
+        members: [person1, person2]
+        state_code: MI
+  output:
+    # Only person1 receives SSI → person1 eligible, person2 not eligible
+    # Couple rate doesn't apply (person2 not eligible) → individual rate $14
+    mi_ssp_eligible: [true, false]
+    mi_ssp_person: [14, 0]
+    mi_ssp: 14
+
+- name: Case 11, Domiciliary Care couple boundary 2019 reflects pre-COLA rate.
+  absolute_error_margin: 0.01
+  period: 2019-01
+  input:
+    people:
+      person1:
+        # $30/mo SSI = $360/yr institutional rate
+        ssi: 360
+        is_ssi_aged_blind_disabled: true
+        is_tax_unit_head_or_spouse: true
+        mi_ssp_living_arrangement: DOMICILIARY_CARE
+      person2:
+        # $30/mo SSI = $360/yr institutional rate
+        ssi: 360
+        is_ssi_aged_blind_disabled: true
+        is_tax_unit_head_or_spouse: true
+        mi_ssp_living_arrangement: DOMICILIARY_CARE
+    marital_units:
+      marital_unit:
+        members: [person1, person2]
+    tax_units:
+      tax_unit:
+        members: [person1, person2]
+    spm_units:
+      spm_unit:
+        members: [person1, person2]
+    households:
+      household:
+        members: [person1, person2]
+        state_code: MI
+  output:
+    # 2019 (pre-2020-01 boundary) Domiciliary Care couple rate = $540
+    # $540 / 2 = $270 each
+    mi_ssp_eligible: [true, true]
+    mi_ssp_person: [270, 270]
+    mi_ssp: 540
+
+- name: Case 12, Domiciliary Care couple at 2020-01 boundary reflects new COLA rate.
+  absolute_error_margin: 0.01
+  period: 2020-01
+  input:
+    people:
+      person1:
+        ssi: 360
+        is_ssi_aged_blind_disabled: true
+        is_tax_unit_head_or_spouse: true
+        mi_ssp_living_arrangement: DOMICILIARY_CARE
+      person2:
+        ssi: 360
+        is_ssi_aged_blind_disabled: true
+        is_tax_unit_head_or_spouse: true
+        mi_ssp_living_arrangement: DOMICILIARY_CARE
+    marital_units:
+      marital_unit:
+        members: [person1, person2]
+    tax_units:
+      tax_unit:
+        members: [person1, person2]
+    spm_units:
+      spm_unit:
+        members: [person1, person2]
+    households:
+      household:
+        members: [person1, person2]
+        state_code: MI
+  output:
+    # 2020-01 boundary: Domiciliary Care couple rate = $565
+    # $565 / 2 = $282.50 each
+    mi_ssp_eligible: [true, true]
+    mi_ssp_person: [282.50, 282.50]
+    mi_ssp: 565
+
+- name: Case 13, Personal Care couple at 2023-12 reflects pre-COLA rate.
+  absolute_error_margin: 0.01
+  period: 2023-01
+  input:
+    people:
+      person1:
+        ssi: 360
+        is_ssi_aged_blind_disabled: true
+        is_tax_unit_head_or_spouse: true
+        mi_ssp_living_arrangement: PERSONAL_CARE
+      person2:
+        ssi: 360
+        is_ssi_aged_blind_disabled: true
+        is_tax_unit_head_or_spouse: true
+        mi_ssp_living_arrangement: PERSONAL_CARE
+    marital_units:
+      marital_unit:
+        members: [person1, person2]
+    tax_units:
+      tax_unit:
+        members: [person1, person2]
+    spm_units:
+      spm_unit:
+        members: [person1, person2]
+    households:
+      household:
+        members: [person1, person2]
+        state_code: MI
+  output:
+    # Pre-2024-01 (2022-2023 era) Personal Care couple rate = $736
+    # $736 / 2 = $368 each
+    mi_ssp_eligible: [true, true]
+    mi_ssp_person: [368, 368]
+    mi_ssp: 736
+
+- name: Case 14, Personal Care couple at 2024-01 boundary reflects new COLA rate.
+  absolute_error_margin: 0.01
+  period: 2024-01
+  input:
+    people:
+      person1:
+        ssi: 360
+        is_ssi_aged_blind_disabled: true
+        is_tax_unit_head_or_spouse: true
+        mi_ssp_living_arrangement: PERSONAL_CARE
+      person2:
+        ssi: 360
+        is_ssi_aged_blind_disabled: true
+        is_tax_unit_head_or_spouse: true
+        mi_ssp_living_arrangement: PERSONAL_CARE
+    marital_units:
+      marital_unit:
+        members: [person1, person2]
+    tax_units:
+      tax_unit:
+        members: [person1, person2]
+    spm_units:
+      spm_unit:
+        members: [person1, person2]
+    households:
+      household:
+        members: [person1, person2]
+        state_code: MI
+  output:
+    # 2024-01 boundary: Personal Care couple rate = $786
+    # $786 / 2 = $393 each
+    mi_ssp_eligible: [true, true]
+    mi_ssp_person: [393, 393]
+    mi_ssp: 786
+
+- name: Case 15, Home for Aged couple at 2025-12 reflects pre-COLA rate.
+  absolute_error_margin: 0.01
+  period: 2025-01
+  input:
+    people:
+      person1:
+        ssi: 360
+        is_ssi_aged_blind_disabled: true
+        is_tax_unit_head_or_spouse: true
+        mi_ssp_living_arrangement: HOME_FOR_AGED
+      person2:
+        ssi: 360
+        is_ssi_aged_blind_disabled: true
+        is_tax_unit_head_or_spouse: true
+        mi_ssp_living_arrangement: HOME_FOR_AGED
+    marital_units:
+      marital_unit:
+        members: [person1, person2]
+    tax_units:
+      tax_unit:
+        members: [person1, person2]
+    spm_units:
+      spm_unit:
+        members: [person1, person2]
+    households:
+      household:
+        members: [person1, person2]
+        state_code: MI
+  output:
+    # Pre-2026-01 (2024-2025 era) Home for Aged couple rate = $829.60
+    # $829.60 / 2 = $414.80 each
+    mi_ssp_eligible: [true, true]
+    mi_ssp_person: [414.80, 414.80]
+    mi_ssp: 829.60
+
+- name: Case 16, Home for Aged couple at 2026-01 boundary reflects new COLA rate.
+  absolute_error_margin: 0.01
+  period: 2026-01
+  input:
+    people:
+      person1:
+        ssi: 360
+        is_ssi_aged_blind_disabled: true
+        is_tax_unit_head_or_spouse: true
+        mi_ssp_living_arrangement: HOME_FOR_AGED
+      person2:
+        ssi: 360
+        is_ssi_aged_blind_disabled: true
+        is_tax_unit_head_or_spouse: true
+        mi_ssp_living_arrangement: HOME_FOR_AGED
+    marital_units:
+      marital_unit:
+        members: [person1, person2]
+    tax_units:
+      tax_unit:
+        members: [person1, person2]
+    spm_units:
+      spm_unit:
+        members: [person1, person2]
+    households:
+      household:
+        members: [person1, person2]
+        state_code: MI
+  output:
+    # 2026-01 boundary: Home for Aged couple rate = $855.60
+    # $855.60 / 2 = $427.80 each
+    mi_ssp_eligible: [true, true]
+    mi_ssp_person: [427.80, 427.80]
+    mi_ssp: 855.60
+
+- name: Case 17, person with ssi=0 and high income gets zero benefit.
+  absolute_error_margin: 0.01
+  period: 2024-01
+  input:
+    people:
+      person1:
+        # High earnings prevent SSI eligibility downstream
+        employment_income: 60_000
+        ssi: 0
+        mi_ssp_living_arrangement: INDEPENDENT_LIVING
+    spm_units:
+      spm_unit:
+        members: [person1]
+    households:
+      household:
+        members: [person1]
+        state_code: MI
+  output:
+    # ssi=0 gate fails → not eligible regardless of LA
+    mi_ssp_eligible: false
+    mi_ssp_person: 0
+    mi_ssp: 0
+
+- name: Case 18, single eligible person in NONE arrangement gets zero.
+  absolute_error_margin: 0.01
+  period: 2024-01
+  input:
+    people:
+      person1:
+        ssi: 11_316
+        mi_ssp_living_arrangement: NONE
+    spm_units:
+      spm_unit:
+        members: [person1]
+    households:
+      household:
+        members: [person1]
+        state_code: MI
+  output:
+    # NONE arrangement fails the in-qualifying-arrangement gate
+    mi_ssp_eligible: false
+    mi_ssp_person: 0
+    mi_ssp: 0
+
+- name: Case 19, single eligible person in Household of Another gets $9.33.
+  absolute_error_margin: 0.01
+  period: 2024-01
+  input:
+    people:
+      person1:
+        is_ssi_eligible: true
+        mi_ssp_living_arrangement: HOUSEHOLD_OF_ANOTHER
+    spm_units:
+      spm_unit:
+        members: [person1]
+    households:
+      household:
+        members: [person1]
+        state_code: MI
+  output:
+    # HoA individual rate = $9.33/mo (frozen)
+    mi_ssp_eligible: true
+    mi_ssp_person: 9.33
+    mi_ssp: 9.33
+
+- name: Case 20, single eligible person in Domiciliary Care gets $87.
+  absolute_error_margin: 0.01
+  period: 2024-01
+  input:
+    people:
+      person1:
+        is_ssi_eligible: true
+        mi_ssp_living_arrangement: DOMICILIARY_CARE
+    spm_units:
+      spm_unit:
+        members: [person1]
+    households:
+      household:
+        members: [person1]
+        state_code: MI
+  output:
+    # Domiciliary Care individual rate = $87/mo (frozen)
+    mi_ssp_eligible: true
+    mi_ssp_person: 87
+    mi_ssp: 87
+
+- name: Case 21, single eligible person in Institution gets $7.
+  absolute_error_margin: 0.01
+  period: 2024-01
+  input:
+    people:
+      person1:
+        is_ssi_eligible: true
+        mi_ssp_living_arrangement: INSTITUTION
+    spm_units:
+      spm_unit:
+        members: [person1]
+    households:
+      household:
+        members: [person1]
+        state_code: MI
+  output:
+    # Institution individual rate = $7/mo (frozen)
+    mi_ssp_eligible: true
+    mi_ssp_person: 7
+    mi_ssp: 7
+
+- name: Case 22, joint SSI couple both in Household of Another gets $13.96 total.
+  absolute_error_margin: 0.01
+  period: 2024-01
+  input:
+    people:
+      person1:
+        ssi: 8_484
+        is_ssi_aged_blind_disabled: true
+        is_tax_unit_head_or_spouse: true
+        mi_ssp_living_arrangement: HOUSEHOLD_OF_ANOTHER
+      person2:
+        ssi: 8_484
+        is_ssi_aged_blind_disabled: true
+        is_tax_unit_head_or_spouse: true
+        mi_ssp_living_arrangement: HOUSEHOLD_OF_ANOTHER
+    marital_units:
+      marital_unit:
+        members: [person1, person2]
+    tax_units:
+      tax_unit:
+        members: [person1, person2]
+    spm_units:
+      spm_unit:
+        members: [person1, person2]
+    households:
+      household:
+        members: [person1, person2]
+        state_code: MI
+  output:
+    # HoA couple rate $13.96 / 2 = $6.98 each
+    mi_ssp_eligible: [true, true]
+    mi_ssp_person: [6.98, 6.98]
+    mi_ssp: 13.96
+
+- name: Case 23, couple with one in Independent Living and one in Personal Care falls back to individual.
+  absolute_error_margin: 0.01
+  period: 2024-01
+  input:
+    people:
+      person1:
+        ssi: 8_484
+        is_ssi_aged_blind_disabled: true
+        is_tax_unit_head_or_spouse: true
+        mi_ssp_living_arrangement: INDEPENDENT_LIVING
+      person2:
+        ssi: 360
+        is_ssi_aged_blind_disabled: true
+        is_tax_unit_head_or_spouse: true
+        mi_ssp_living_arrangement: PERSONAL_CARE
+    marital_units:
+      marital_unit:
+        members: [person1, person2]
+    tax_units:
+      tax_unit:
+        members: [person1, person2]
+    spm_units:
+      spm_unit:
+        members: [person1, person2]
+    households:
+      household:
+        members: [person1, person2]
+        state_code: MI
+  output:
+    # Mismatched LAs → individual rates
+    # person1: IL individual = $14, person2: Personal Care individual = $157.50
+    mi_ssp_eligible: [true, true]
+    mi_ssp_person: [14, 157.50]
+    # SPM unit total = $14 + $157.50 = $171.50
+    mi_ssp: 171.50
+
+- name: Case 24, three SSI recipients in same household sum correctly.
+  absolute_error_margin: 0.01
+  period: 2024-01
+  input:
+    people:
+      person1:
+        is_ssi_eligible: true
+        is_ssi_aged_blind_disabled: true
+        is_tax_unit_head_or_spouse: true
+        mi_ssp_living_arrangement: INDEPENDENT_LIVING
+      person2:
+        is_ssi_eligible: true
+        is_ssi_aged_blind_disabled: true
+        is_tax_unit_head_or_spouse: true
+        mi_ssp_living_arrangement: INDEPENDENT_LIVING
+      person3:
+        # Third SSI recipient (e.g., adult relative) - not in marital unit
+        is_ssi_eligible: true
+        mi_ssp_living_arrangement: INDEPENDENT_LIVING
+    marital_units:
+      marital_unit:
+        members: [person1, person2]
+      marital_unit2:
+        members: [person3]
+    tax_units:
+      tax_unit:
+        members: [person1, person2]
+      tax_unit2:
+        members: [person3]
+    spm_units:
+      spm_unit:
+        members: [person1, person2, person3]
+    households:
+      household:
+        members: [person1, person2, person3]
+        state_code: MI
+  output:
+    # person1+person2 = couple rate $21 → $10.50 each
+    # person3 = individual rate $14
+    mi_ssp_eligible: [true, true, true]
+    mi_ssp_person: [10.50, 10.50, 14]
+    # SPM unit total = $10.50 + $10.50 + $14 = $35
+    mi_ssp: 35
+
+- name: Case 25, non-Michigan resident SSI recipient gets zero MI SSP.
+  absolute_error_margin: 0.01
+  period: 2024-01
+  input:
+    people:
+      person1:
+        ssi: 11_316
+        mi_ssp_living_arrangement: INDEPENDENT_LIVING
+    spm_units:
+      spm_unit:
+        members: [person1]
+    households:
+      household:
+        members: [person1]
+        # Non-MI state → defined_for=StateCode.MI zeros mi_ssp
+        state_code: CA
+  output:
+    # defined_for filter on mi_ssp returns 0 outside Michigan
+    mi_ssp: 0
+
+- name: Case 26, child SSI recipient gets Independent Living individual rate.
+  absolute_error_margin: 0.01
+  period: 2024-01
+  input:
+    people:
+      person1:
+        age: 8
+        is_disabled: true
+        # Child receives federal SSI at 2024 individual FBR
+        # $943/mo = $11,316/yr
+        ssi: 11_316
+        # mi_ssp_living_arrangement defaults to INDEPENDENT_LIVING
+    spm_units:
+      spm_unit:
+        members: [person1]
+    households:
+      household:
+        members: [person1]
+        state_code: MI
+  output:
+    # BEM 660 covers all SSI recipients including children; RFT 248
+    # "Eligible Child" rate equals the IL individual rate ($14/mo).
+    mi_ssp_eligible: true
+    mi_ssp_individual_amount: 14
+    mi_ssp_person: 14
+    mi_ssp: 14
+
+- name: Case 27, Independent Living person with no regular federal SSI payment is ineligible.
+  absolute_error_margin: 0.01
+  period: 2024-01
+  input:
+    people:
+      person1:
+        age: 70
+        is_ssi_aged_blind_disabled: true
+        # $30,000/yr social security retirement = $2,500/mo. After the
+        # $20 general unearned income exclusion, annual countable
+        # unearned ≈ $29,760. Uncapped SSI = $11,316 - $29,760 = -$18,444.
+        # Monthly spillover = -uncapped_ssi/12 ≈ $1,537. BEM 660 limits
+        # MDHHS-issued Independent Living SSPs to months with a regular
+        # first-of-month federal SSI benefit, so this person is not
+        # eligible for the MDHHS-issued payment.
+        social_security_retirement: 30_000
+        mi_ssp_living_arrangement: INDEPENDENT_LIVING
+    spm_units:
+      spm_unit:
+        members: [person1]
+    households:
+      household:
+        members: [person1]
+        state_code: MI
+  output:
+    # MDHHS-administered Independent Living category fails the federal
+    # SSI payment gate.
+    mi_ssp_eligible: false
+    mi_ssp_person: 0
+    mi_ssp: 0
+
+- name: Case 28, Personal Care recipient in spillover window receives partial SSP.
+  absolute_error_margin: 0.01
+  period: 2024-01
+  input:
+    people:
+      person1:
+        is_ssi_eligible: true
+        # uncapped_ssi annual = -600 → monthly spillover = $50.
+        # Personal Care SSP base = $157.50/mo. Result = max_(0, 157.50 - 50) = $107.50.
+        uncapped_ssi: -600
+        mi_ssp_living_arrangement: PERSONAL_CARE
+    spm_units:
+      spm_unit:
+        members: [person1]
+    households:
+      household:
+        members: [person1]
+        state_code: MI
+  output:
+    # Federal SSI exhausted ($0) but state supplement only partially
+    # spilled into → recipient gets $107.50 SSP.
+    mi_ssp_eligible: true
+    mi_ssp_person: 107.50
+    mi_ssp: 107.50
diff --git a/policyengine_us/tests/policy/baseline/gov/states/mi/mdhhs/ssp/mi_ssp.yaml b/policyengine_us/tests/policy/baseline/gov/states/mi/mdhhs/ssp/mi_ssp.yaml
new file mode 100644
index 00000000000..09b9a812f14
--- /dev/null
+++ b/policyengine_us/tests/policy/baseline/gov/states/mi/mdhhs/ssp/mi_ssp.yaml
@@ -0,0 +1,89 @@
+- name: Case 1, single eligible person sums to individual amount.
+  absolute_error_margin: 0.01
+  period: 2024-01
+  input:
+    people:
+      person1:
+        is_ssi_eligible: true
+        mi_ssp_living_arrangement: INDEPENDENT_LIVING
+    spm_units:
+      spm_unit:
+        members: [person1]
+    households:
+      household:
+        members: [person1]
+        state_code: MI
+  output:
+    # Single person IL = $14
+    mi_ssp: 14
+
+- name: Case 2, joint couple in same arrangement sums per-person amounts.
+  absolute_error_margin: 0.01
+  period: 2024-01
+  input:
+    people:
+      person1:
+        # $707/mo SSI = $8,484/yr couple half
+        ssi: 8_484
+        is_ssi_aged_blind_disabled: true
+        is_tax_unit_head_or_spouse: true
+        mi_ssp_living_arrangement: INDEPENDENT_LIVING
+      person2:
+        # $707/mo SSI = $8,484/yr couple half
+        ssi: 8_484
+        is_ssi_aged_blind_disabled: true
+        is_tax_unit_head_or_spouse: true
+        mi_ssp_living_arrangement: INDEPENDENT_LIVING
+    marital_units:
+      marital_unit:
+        members: [person1, person2]
+    tax_units:
+      tax_unit:
+        members: [person1, person2]
+    spm_units:
+      spm_unit:
+        members: [person1, person2]
+    households:
+      household:
+        members: [person1, person2]
+        state_code: MI
+  output:
+    # Couple rate $21 total ($10.50 + $10.50)
+    mi_ssp: 21
+
+- name: Case 3, no one receives SSI so SPM unit total is zero.
+  absolute_error_margin: 0.01
+  period: 2024-01
+  input:
+    people:
+      person1:
+        ssi: 0
+        mi_ssp_living_arrangement: INDEPENDENT_LIVING
+    spm_units:
+      spm_unit:
+        members: [person1]
+    households:
+      household:
+        members: [person1]
+        state_code: MI
+  output:
+    mi_ssp: 0
+
+- name: Case 4, non-Michigan SPM unit gets zero.
+  absolute_error_margin: 0.01
+  period: 2024-01
+  input:
+    people:
+      person1:
+        # $943/mo SSI = $11,316/yr individual FBR
+        ssi: 11_316
+        mi_ssp_living_arrangement: INDEPENDENT_LIVING
+    spm_units:
+      spm_unit:
+        members: [person1]
+    households:
+      household:
+        members: [person1]
+        state_code: OH
+  output:
+    mi_ssp: 0
diff --git a/policyengine_us/tests/policy/baseline/gov/states/mi/mdhhs/ssp/mi_ssp_couple_amount.yaml b/policyengine_us/tests/policy/baseline/gov/states/mi/mdhhs/ssp/mi_ssp_couple_amount.yaml
new file mode 100644
index 00000000000..0458e1f38fe
--- /dev/null
+++ b/policyengine_us/tests/policy/baseline/gov/states/mi/mdhhs/ssp/mi_ssp_couple_amount.yaml
@@ -0,0 +1,111 @@
+- name: Case 1, Independent Living couple amount frozen at $21 total.
+  absolute_error_margin: 0.01
+  period: 2024-01
+  input:
+    people:
+      person1:
+        is_ssi_eligible: true
+        mi_ssp_living_arrangement: INDEPENDENT_LIVING
+    households:
+      household:
+        members: [person1]
+        state_code: MI
+  output:
+    # $21 / 2 = $10.50 per person
+    mi_ssp_couple_amount: 10.50
+
+- name: Case 2, Household of Another couple amount frozen at $13.96 total.
+  absolute_error_margin: 0.01
+  period: 2024-01
+  input:
+    people:
+      person1:
+        is_ssi_eligible: true
+        mi_ssp_living_arrangement: HOUSEHOLD_OF_ANOTHER
+    households:
+      household:
+        members: [person1]
+        state_code: MI
+  output:
+    # $13.96 / 2 = $6.98 per person
+    mi_ssp_couple_amount: 6.98
+
+- name: Case 3, Domiciliary Care couple in 2024 uses 2024 rate.
+  absolute_error_margin: 0.01
+  period: 2024-01
+  input:
+    people:
+      person1:
+        is_ssi_eligible: true
+        mi_ssp_living_arrangement: DOMICILIARY_CARE
+    households:
+      household:
+        members: [person1]
+        state_code: MI
+  output:
+    # 2024 rate $645 / 2 = $322.50 per person
+    mi_ssp_couple_amount: 322.50
+
+- name: Case 4, Personal Care couple in 2026 uses 2026 rate.
+  absolute_error_margin: 0.01
+  period: 2026-01
+  input:
+    people:
+      person1:
+        is_ssi_eligible: true
+        mi_ssp_living_arrangement: PERSONAL_CARE
+    households:
+      household:
+        members: [person1]
+        state_code: MI
+  output:
+    # 2026 rate $812 / 2 = $406 per person
+    mi_ssp_couple_amount: 406
+
+- name: Case 5, Home for Aged couple in 2020 uses 2020 rate.
+  absolute_error_margin: 0.01
+  period: 2020-01
+  input:
+    people:
+      person1:
+        is_ssi_eligible: true
+        mi_ssp_living_arrangement: HOME_FOR_AGED
+    households:
+      household:
+        members: [person1]
+        state_code: MI
+  output:
+    # 2020 rate $749.60 / 2 = $374.80 per person
+    mi_ssp_couple_amount: 374.80
+
+- name: Case 6, Institution couple frozen at $14 total.
+  absolute_error_margin: 0.01
+  period: 2024-01
+  input:
+    people:
+      person1:
+        is_ssi_eligible: true
+        mi_ssp_living_arrangement: INSTITUTION
+    households:
+      household:
+        members: [person1]
+        state_code: MI
+  output:
+    # $14 / 2 = $7 per person
+    mi_ssp_couple_amount: 7
+
+- name: Case 7, Domiciliary Care couple in 2016 uses 2016 rate.
+  absolute_error_margin: 0.01
+  period: 2016-01
+  input:
+    people:
+      person1:
+        is_ssi_eligible: true
+        mi_ssp_living_arrangement: DOMICILIARY_CARE
+    households:
+      household:
+        members: [person1]
+        state_code: MI
+  output:
+    # 2016 rate $540 / 2 = $270 per person
+    mi_ssp_couple_amount: 270
diff --git a/policyengine_us/tests/policy/baseline/gov/states/mi/mdhhs/ssp/mi_ssp_couple_eligible.yaml b/policyengine_us/tests/policy/baseline/gov/states/mi/mdhhs/ssp/mi_ssp_couple_eligible.yaml
new file mode 100644
index 00000000000..2d5b7ef3146
--- /dev/null
+++ b/policyengine_us/tests/policy/baseline/gov/states/mi/mdhhs/ssp/mi_ssp_couple_eligible.yaml
@@ -0,0 +1,105 @@
+- name: Case 1, joint claim with both eligible in same LA returns true.
+  period: 2024-01
+  input:
+    people:
+      person1:
+        is_ssi_aged_blind_disabled: true
+        is_tax_unit_head_or_spouse: true
+        mi_ssp_living_arrangement: INDEPENDENT_LIVING
+      person2:
+        is_ssi_aged_blind_disabled: true
+        is_tax_unit_head_or_spouse: true
+        mi_ssp_living_arrangement: INDEPENDENT_LIVING
+    marital_units:
+      marital_unit:
+        members: [person1, person2]
+    tax_units:
+      tax_unit:
+        members: [person1, person2]
+    households:
+      household:
+        members: [person1, person2]
+        state_code: MI
+  output:
+    mi_ssp_couple_eligible: [true, true]
+
+- name: Case 2, joint claim with both eligible but different LAs returns false.
+  period: 2024-01
+  input:
+    people:
+      person1:
+        is_ssi_aged_blind_disabled: true
+        is_tax_unit_head_or_spouse: true
+        mi_ssp_living_arrangement: INDEPENDENT_LIVING
+      person2:
+        is_ssi_aged_blind_disabled: true
+        is_tax_unit_head_or_spouse: true
+        mi_ssp_living_arrangement: HOUSEHOLD_OF_ANOTHER
+    marital_units:
+      marital_unit:
+        members: [person1, person2]
+    tax_units:
+      tax_unit:
+        members: [person1, person2]
+    households:
+      household:
+        members: [person1, person2]
+        state_code: MI
+  output:
+    mi_ssp_couple_eligible: [false, false]
+
+- name: Case 3, joint claim with only one SSI-eligible spouse returns false.
+  period: 2024-01
+  input:
+    people:
+      person1:
+        is_ssi_aged_blind_disabled: true
+        is_tax_unit_head_or_spouse: true
+        mi_ssp_living_arrangement: INDEPENDENT_LIVING
+      person2:
+        is_ssi_aged_blind_disabled: false
+        is_ssi_eligible: false
+        is_tax_unit_head_or_spouse: true
+        mi_ssp_living_arrangement: INDEPENDENT_LIVING
+    marital_units:
+      marital_unit:
+        members: [person1, person2]
+    tax_units:
+      tax_unit:
+        members: [person1, person2]
+    households:
+      household:
+        members: [person1, person2]
+        state_code: MI
+  output:
+    # person2 is filtered to false by defined_for=mi_ssp_eligible;
+    # person1 fails the both_eligible (marital_unit.sum == 2) gate.
+    mi_ssp_couple_eligible: [false, false]
+
+- name: Case 4, two SSI recipients in same LA but not joint claim returns false.
+  period: 2024-01
+  input:
+    people:
+      person1:
+        is_ssi_aged_blind_disabled: true
+        mi_ssp_living_arrangement: INDEPENDENT_LIVING
+      person2:
+        is_ssi_aged_blind_disabled: true
+        mi_ssp_living_arrangement: INDEPENDENT_LIVING
+    marital_units:
+      marital_unit1:
+        members: [person1]
+      marital_unit2:
+        members: [person2]
+    tax_units:
+      tax_unit1:
+        members: [person1]
+      tax_unit2:
+        members: [person2]
+    households:
+      household:
+        members: [person1, person2]
+        state_code: MI
+  output:
+    # Separate marital units → ssi_claim_is_joint = false → couple gate fails.
+    mi_ssp_couple_eligible: [false, false]
diff --git a/policyengine_us/tests/policy/baseline/gov/states/mi/mdhhs/ssp/mi_ssp_eligible.yaml b/policyengine_us/tests/policy/baseline/gov/states/mi/mdhhs/ssp/mi_ssp_eligible.yaml
new file mode 100644
index 00000000000..d99d2729ce6
--- /dev/null
+++ b/policyengine_us/tests/policy/baseline/gov/states/mi/mdhhs/ssp/mi_ssp_eligible.yaml
@@ -0,0 +1,74 @@
+- name: Case 1, Michigan resident categorically SSI-eligible is eligible.
+  period: 2024-01
+  input:
+    people:
+      person1:
+        is_ssi_eligible: true
+    households:
+      household:
+        members: [person1]
+        state_code: MI
+  output:
+    mi_ssp_eligible: true
+
+- name: Case 2, Michigan resident not SSI-eligible is ineligible.
+  period: 2024-01
+  input:
+    people:
+      person1:
+        is_ssi_eligible: false
+    households:
+      household:
+        members: [person1]
+        state_code: MI
+  output:
+    mi_ssp_eligible: false
+
+- name: Case 3, non-Michigan resident categorically SSI-eligible is ineligible.
+  period: 2024-01
+  input:
+    people:
+      person1:
+        is_ssi_eligible: true
+    households:
+      household:
+        members: [person1]
+        state_code: OH
+  output:
+    mi_ssp_eligible: false
+
+- name: Case 4, MDHHS-administered category with no federal SSI payment is ineligible.
+  period: 2024-01
+  input:
+    people:
+      person1:
+        is_ssi_aged_blind_disabled: true
+        is_ssi_eligible: true
+        ssi: 0
+        mi_ssp_living_arrangement: INDEPENDENT_LIVING
+    households:
+      household:
+        members: [person1]
+        state_code: MI
+  output:
+    # BEM 660 limits MDHHS-issued SSPs to months with a regular
+    # first-of-month federal SSI benefit.
+    mi_ssp_eligible: false
+
+- name: Case 5, SSA-administered facility category keeps categorical spillover eligibility.
+  period: 2024-01
+  input:
+    people:
+      person1:
+        is_ssi_aged_blind_disabled: true
+        is_ssi_eligible: true
+        ssi: 0
+        mi_ssp_living_arrangement: PERSONAL_CARE
+    households:
+      household:
+        members: [person1]
+        state_code: MI
+  output:
+    # SSA-administered facility categories use the combined SSI/SSP
+    # income calculation; mi_ssp_person applies the spillover reduction.
+    mi_ssp_eligible: true
diff --git a/policyengine_us/tests/policy/baseline/gov/states/mi/mdhhs/ssp/mi_ssp_individual_amount.yaml b/policyengine_us/tests/policy/baseline/gov/states/mi/mdhhs/ssp/mi_ssp_individual_amount.yaml
new file mode 100644
index 00000000000..c36363ae236
--- /dev/null
+++ b/policyengine_us/tests/policy/baseline/gov/states/mi/mdhhs/ssp/mi_ssp_individual_amount.yaml
@@ -0,0 +1,104 @@
+- name: Case 1, Independent Living looks up individual rate.
+  absolute_error_margin: 0.01
+  period: 2024-01
+  input:
+    people:
+      person1:
+        is_ssi_eligible: true
+        mi_ssp_living_arrangement: INDEPENDENT_LIVING
+    households:
+      household:
+        members: [person1]
+        state_code: MI
+  output:
+    mi_ssp_individual_amount: 14
+
+- name: Case 2, Household of Another looks up individual rate.
+  absolute_error_margin: 0.01
+  period: 2024-01
+  input:
+    people:
+      person1:
+        is_ssi_eligible: true
+        mi_ssp_living_arrangement: HOUSEHOLD_OF_ANOTHER
+    households:
+      household:
+        members: [person1]
+        state_code: MI
+  output:
+    mi_ssp_individual_amount: 9.33
+
+- name: Case 3, Domiciliary Care looks up individual rate.
+  absolute_error_margin: 0.01
+  period: 2024-01
+  input:
+    people:
+      person1:
+        is_ssi_eligible: true
+        mi_ssp_living_arrangement: DOMICILIARY_CARE
+    households:
+      household:
+        members: [person1]
+        state_code: MI
+  output:
+    mi_ssp_individual_amount: 87
+
+- name: Case 4, Personal Care looks up individual rate.
+  absolute_error_margin: 0.01
+  period: 2024-01
+  input:
+    people:
+      person1:
+        is_ssi_eligible: true
+        mi_ssp_living_arrangement: PERSONAL_CARE
+    households:
+      household:
+        members: [person1]
+        state_code: MI
+  output:
+    mi_ssp_individual_amount: 157.50
+
+- name: Case 5, Home for Aged looks up individual rate.
+  absolute_error_margin: 0.01
+  period: 2024-01
+  input:
+    people:
+      person1:
+        is_ssi_eligible: true
+        mi_ssp_living_arrangement: HOME_FOR_AGED
+    households:
+      household:
+        members: [person1]
+        state_code: MI
+  output:
+    mi_ssp_individual_amount: 179.30
+
+- name: Case 6, Institution looks up individual rate.
+  absolute_error_margin: 0.01
+  period: 2024-01
+  input:
+    people:
+      person1:
+        is_ssi_eligible: true
+        mi_ssp_living_arrangement: INSTITUTION
+    households:
+      household:
+        members: [person1]
+        state_code: MI
+  output:
+    mi_ssp_individual_amount: 7
+
+- name: Case 7, NONE arrangement returns zero.
+  absolute_error_margin: 0.01
+  period: 2024-01
+  input:
+    people:
+      person1:
+        is_ssi_eligible: true
+        mi_ssp_living_arrangement: NONE
+    households:
+      household:
+        members: [person1]
+        state_code: MI
+  output:
+    mi_ssp_individual_amount: 0
diff --git a/policyengine_us/tests/policy/baseline/gov/states/mi/mdhhs/ssp/mi_ssp_payment_category.yaml b/policyengine_us/tests/policy/baseline/gov/states/mi/mdhhs/ssp/mi_ssp_payment_category.yaml
new file mode 100644
index 00000000000..415c59ec525
--- /dev/null
+++ b/policyengine_us/tests/policy/baseline/gov/states/mi/mdhhs/ssp/mi_ssp_payment_category.yaml
@@ -0,0 +1,72 @@
+- name: Case 1, default Independent Living input passes through to category.
+  period: 2024-01
+  input:
+    people:
+      person1:
+        # ssi_federal_living_arrangement defaults to OWN_HOUSEHOLD;
+        # mi_ssp_living_arrangement defaults to INDEPENDENT_LIVING.
+        age: 70
+    households:
+      household:
+        members: [person1]
+        state_code: MI
+  output:
+    mi_ssp_payment_category: INDEPENDENT_LIVING
+
+- name: Case 2, federal MEDICAL_TREATMENT_FACILITY overrides input to INSTITUTION.
+  period: 2024-01
+  input:
+    people:
+      person1:
+        ssi_federal_living_arrangement: MEDICAL_TREATMENT_FACILITY
+        # Even if user sets a different MI category, federal classification wins.
+        mi_ssp_living_arrangement: INDEPENDENT_LIVING
+    households:
+      household:
+        members: [person1]
+        state_code: MI
+  output:
+    mi_ssp_payment_category: INSTITUTION
+
+- name: Case 3, federal ANOTHER_PERSONS_HOUSEHOLD overrides input to HOUSEHOLD_OF_ANOTHER.
+  period: 2024-01
+  input:
+    people:
+      person1:
+        ssi_federal_living_arrangement: ANOTHER_PERSONS_HOUSEHOLD
+        mi_ssp_living_arrangement: INDEPENDENT_LIVING
+    households:
+      household:
+        members: [person1]
+        state_code: MI
+  output:
+    mi_ssp_payment_category: HOUSEHOLD_OF_ANOTHER
+
+- name: Case 4, MI-specific Personal Care input passes through when federal LA does not override.
+  period: 2024-01
+  input:
+    people:
+      person1:
+        ssi_federal_living_arrangement: OWN_HOUSEHOLD
+        mi_ssp_living_arrangement: PERSONAL_CARE
+    households:
+      household:
+        members: [person1]
+        state_code: MI
+  output:
+    mi_ssp_payment_category: PERSONAL_CARE
+
+- name: Case 5, federal CHILD_IN_PARENTAL_HOUSEHOLD does not override input.
+  period: 2024-01
+  input:
+    people:
+      person1:
+        age: 12
+        ssi_federal_living_arrangement: CHILD_IN_PARENTAL_HOUSEHOLD
+        mi_ssp_living_arrangement: INDEPENDENT_LIVING
+    households:
+      household:
+        members: [person1]
+        state_code: MI
+  output:
+    mi_ssp_payment_category: INDEPENDENT_LIVING
diff --git a/policyengine_us/tests/policy/baseline/gov/states/mi/mdhhs/ssp/mi_ssp_person.yaml b/policyengine_us/tests/policy/baseline/gov/states/mi/mdhhs/ssp/mi_ssp_person.yaml
new file mode 100644
index 00000000000..e955392fc05
--- /dev/null
+++ b/policyengine_us/tests/policy/baseline/gov/states/mi/mdhhs/ssp/mi_ssp_person.yaml
@@ -0,0 +1,124 @@
+- name: Case 1, single eligible person uses individual amount.
+  absolute_error_margin: 0.01
+  period: 2024-01
+  input:
+    people:
+      person1:
+        is_ssi_eligible: true
+        mi_ssp_living_arrangement: INDEPENDENT_LIVING
+    households:
+      household:
+        members: [person1]
+        state_code: MI
+  output:
+    # Individual rate for IL = $14
+    mi_ssp_person: 14
+
+- name: Case 2, ineligible person gets zero regardless of arrangement.
+  absolute_error_margin: 0.01
+  period: 2024-01
+  input:
+    people:
+      person1:
+        ssi: 0
+        mi_ssp_living_arrangement: INDEPENDENT_LIVING
+    households:
+      household:
+        members: [person1]
+        state_code: MI
+  output:
+    mi_ssp_person: 0
+
+- name: Case 3, joint SSI couple in same arrangement gets couple amount.
+  absolute_error_margin: 0.01
+  period: 2024-01
+  input:
+    people:
+      person1:
+        # $707/mo SSI = $8,484/yr couple half
+        ssi: 8_484
+        is_ssi_aged_blind_disabled: true
+        is_tax_unit_head_or_spouse: true
+        mi_ssp_living_arrangement: INDEPENDENT_LIVING
+      person2:
+        # $707/mo SSI = $8,484/yr couple half
+        ssi: 8_484
+        is_ssi_aged_blind_disabled: true
+        is_tax_unit_head_or_spouse: true
+        mi_ssp_living_arrangement: INDEPENDENT_LIVING
+    marital_units:
+      marital_unit:
+        members: [person1, person2]
+    tax_units:
+      tax_unit:
+        members: [person1, person2]
+    households:
+      household:
+        members: [person1, person2]
+        state_code: MI
+  output:
+    # Couple rate $21 / 2 = $10.50 per person
+    mi_ssp_person: [10.50, 10.50]
+
+- name: Case 4, joint SSI couple in mismatched arrangements falls back to individual.
+  absolute_error_margin: 0.01
+  period: 2024-01
+  input:
+    people:
+      person1:
+        # $707/mo SSI = $8,484/yr couple half
+        ssi: 8_484
+        is_ssi_aged_blind_disabled: true
+        is_tax_unit_head_or_spouse: true
+        mi_ssp_living_arrangement: INDEPENDENT_LIVING
+      person2:
+        # $707/mo SSI = $8,484/yr couple half
+        ssi: 8_484
+        is_ssi_aged_blind_disabled: true
+        is_tax_unit_head_or_spouse: true
+        mi_ssp_living_arrangement: HOUSEHOLD_OF_ANOTHER
+    marital_units:
+      marital_unit:
+        members: [person1, person2]
+    tax_units:
+      tax_unit:
+        members: [person1, person2]
+    households:
+      household:
+        members: [person1, person2]
+        state_code: MI
+  output:
+    # Different arrangements → each person gets their individual rate
+    # person1: IL individual = $14, person2: HoA individual = $9.33
+    mi_ssp_person: [14, 9.33]
+
+- name: Case 5, only one spouse SSI-eligible falls back to individual amounts.
+  absolute_error_margin: 0.01
+  period: 2024-01
+  input:
+    people:
+      person1:
+        # $943/mo SSI = $11,316/yr individual FBR
+        ssi: 11_316
+        is_ssi_aged_blind_disabled: true
+        is_tax_unit_head_or_spouse: true
+        mi_ssp_living_arrangement: INDEPENDENT_LIVING
+      person2:
+        ssi: 0
+        is_ssi_aged_blind_disabled: false
+        is_tax_unit_head_or_spouse: true
+        mi_ssp_living_arrangement: INDEPENDENT_LIVING
+    marital_units:
+      marital_unit:
+        members: [person1, person2]
+    tax_units:
+      tax_unit:
+        members: [person1, person2]
+    households:
+      household:
+        members: [person1, person2]
+        state_code: MI
+  output:
+    # person1 eligible → individual rate $14
+    # person2 not SSI receiving → not eligible → $0
+    mi_ssp_person: [14, 0]
diff --git a/policyengine_us/variables/gov/states/mi/mdhhs/ssp/mi_ssp.py b/policyengine_us/variables/gov/states/mi/mdhhs/ssp/mi_ssp.py
new file mode 100644
index 00000000000..e0c4125c2c7
--- /dev/null
+++ b/policyengine_us/variables/gov/states/mi/mdhhs/ssp/mi_ssp.py
@@ -0,0 +1,19 @@
+from policyengine_us.model_api import *
+
+
+class mi_ssp(Variable):
+    value_type = float
+    entity = SPMUnit
+    label = "Michigan State Supplementary Payment"
+    unit = USD
+    definition_period = MONTH
+    defined_for = StateCode.MI
+    reference = (
+        "https://mdhhs-pres-prod.michigan.gov/olmweb/EX/BP/Public/BEM/660.pdf#page=2",
+        "https://mdhhs-pres-prod.michigan.gov/olmweb/EX/BP/Public/BEM/660.pdf#page=4",
+        "https://mdhhs-pres-prod.michigan.gov/olmweb/ex/RF/Public/RFT/248.pdf#page=2",
+        "https://www.legislature.mi.gov/Laws/MCL?objectName=mcl-400-10",
+        "https://www.ssa.gov/policy/docs/progdesc/ssi_st_asst/2011/mi.html",
+    )
+
+    adds = ["mi_ssp_person"]
diff --git a/policyengine_us/variables/gov/states/mi/mdhhs/ssp/mi_ssp_couple_amount.py b/policyengine_us/variables/gov/states/mi/mdhhs/ssp/mi_ssp_couple_amount.py
new file mode 100644
index 00000000000..93862411ad2
--- /dev/null
+++ b/policyengine_us/variables/gov/states/mi/mdhhs/ssp/mi_ssp_couple_amount.py
@@ -0,0 +1,20 @@
+from policyengine_us.model_api import *
+
+
+class mi_ssp_couple_amount(Variable):
+    value_type = float
+    entity = Person
+    label = "Michigan SSP couple payment amount per spouse"
+    unit = USD
+    definition_period = MONTH
+    defined_for = "mi_ssp_eligible"
+    reference = (
+        "https://mdhhs-pres-prod.michigan.gov/olmweb/EX/BP/Public/BEM/660.pdf#page=2",
+        "https://mdhhs-pres-prod.michigan.gov/olmweb/EX/BP/Public/BEM/660.pdf#page=4",
+        "https://mdhhs-pres-prod.michigan.gov/olmweb/ex/RF/Public/RFT/248.pdf#page=2",
+    )
+
+    def formula(person, period, parameters):
+        category = person("mi_ssp_payment_category", period)
+        p = parameters(period).gov.states.mi.mdhhs.ssp.payment
+        return p.couple[category] / 2
diff --git a/policyengine_us/variables/gov/states/mi/mdhhs/ssp/mi_ssp_couple_eligible.py b/policyengine_us/variables/gov/states/mi/mdhhs/ssp/mi_ssp_couple_eligible.py
new file mode 100644
index 00000000000..f356ddf099f
--- /dev/null
+++ b/policyengine_us/variables/gov/states/mi/mdhhs/ssp/mi_ssp_couple_eligible.py
@@ -0,0 +1,40 @@
+from policyengine_us.model_api import *
+from policyengine_us.variables.gov.states.mi.mdhhs.ssp.mi_ssp_living_arrangement import (
+    MISSPLivingArrangement,
+)
+
+
+class mi_ssp_couple_eligible(Variable):
+    value_type = bool
+    entity = Person
+    label = "Michigan SSP couple rate applies"
+    definition_period = MONTH
+    defined_for = "mi_ssp_eligible"
+    reference = (
+        "https://mdhhs-pres-prod.michigan.gov/olmweb/EX/BP/Public/BEM/660.pdf#page=1",
+        "https://mdhhs-pres-prod.michigan.gov/olmweb/EX/BP/Public/BEM/660.pdf#page=4",
+        "https://mdhhs-pres-prod.michigan.gov/olmweb/ex/RF/Public/RFT/248.pdf#page=2",
+    )
+
+    def formula(person, period, parameters):
+        joint_claim = person("ssi_claim_is_joint", period.this_year)
+        eligible = person("mi_ssp_eligible", period)
+        # Summing the same variable used in defined_for is safe here; if a
+        # future contributor swaps to summing a different variable across
+        # the marital unit, the defined_for filter could silently halve
+        # the result.
+        both_eligible = person.marital_unit.sum(eligible) == 2
+        category = person("mi_ssp_payment_category", period)
+        qualifying_arrangements = [
+            value
+            for value in MISSPLivingArrangement
+            if value != MISSPLivingArrangement.NONE
+        ]
+        both_same_arrangement = (
+            sum(
+                person.marital_unit.sum(category == value) == 2
+                for value in qualifying_arrangements
+            )
+            > 0
+        )
+        return joint_claim & both_eligible & both_same_arrangement
diff --git a/policyengine_us/variables/gov/states/mi/mdhhs/ssp/mi_ssp_eligible.py b/policyengine_us/variables/gov/states/mi/mdhhs/ssp/mi_ssp_eligible.py
new file mode 100644
index 00000000000..43625dd2409
--- /dev/null
+++ b/policyengine_us/variables/gov/states/mi/mdhhs/ssp/mi_ssp_eligible.py
@@ -0,0 +1,41 @@
+from policyengine_us.model_api import *
+from policyengine_us.variables.gov.states.mi.mdhhs.ssp.mi_ssp_living_arrangement import (
+    MISSPLivingArrangement,
+)
+
+
+class mi_ssp_eligible(Variable):
+    value_type = bool
+    entity = Person
+    label = "Michigan SSP eligible"
+    definition_period = MONTH
+    defined_for = StateCode.MI
+    reference = (
+        "https://mdhhs-pres-prod.michigan.gov/olmweb/EX/BP/Public/BEM/660.pdf#page=4",
+        "https://mdhhs-pres-prod.michigan.gov/olmweb/EX/BP/Public/BEM/660.pdf#page=2",
+    )
+
+    def formula(person, period, parameters):
+        # MDHHS-administered categories (Independent Living and Household
+        # of Another) require an actual regular federal SSI check per BEM
+        # 660.
+        # SSA-administered Adult Foster Care (Domiciliary, Personal) and
+        # Home for the Aged/Institution categories use categorical
+        # eligibility plus the spillover reduction in mi_ssp_person, per
+        # the SSA baseline: countable income deducts from federal SSI
+        # first, and any remaining countable income reduces the state
+        # supplement.
+        # We don't track section 1619 working-disabled status at the moment.
+        category = person("mi_ssp_payment_category", period)
+        is_strict_category = (category == MISSPLivingArrangement.INDEPENDENT_LIVING) | (
+            category == MISSPLivingArrangement.HOUSEHOLD_OF_ANOTHER
+        )
+        receives_ssi = person("ssi", period) > 0
+        is_ssi_eligible = person("is_ssi_eligible", period.this_year)
+        arrangement_gate = where(
+            is_strict_category,
+            receives_ssi,
+            is_ssi_eligible,
+        )
+        in_qualifying_arrangement = category != MISSPLivingArrangement.NONE
+        return arrangement_gate & in_qualifying_arrangement
diff --git a/policyengine_us/variables/gov/states/mi/mdhhs/ssp/mi_ssp_individual_amount.py b/policyengine_us/variables/gov/states/mi/mdhhs/ssp/mi_ssp_individual_amount.py
new file mode 100644
index 00000000000..0867c3a428e
--- /dev/null
+++ b/policyengine_us/variables/gov/states/mi/mdhhs/ssp/mi_ssp_individual_amount.py
@@ -0,0 +1,18 @@
+from policyengine_us.model_api import *
+
+
+class mi_ssp_individual_amount(Variable):
+    value_type = float
+    entity = Person
+    label = "Michigan SSP individual payment amount"
+    unit = USD
+    definition_period = MONTH
+    defined_for = "mi_ssp_eligible"
+    reference = (
+        "https://mdhhs-pres-prod.michigan.gov/olmweb/ex/RF/Public/RFT/248.pdf#page=2",
+    )
+
+    def formula(person, period, parameters):
+        category = person("mi_ssp_payment_category", period)
+        p = parameters(period).gov.states.mi.mdhhs.ssp.payment
+        return p.individual[category]
diff --git a/policyengine_us/variables/gov/states/mi/mdhhs/ssp/mi_ssp_living_arrangement.py b/policyengine_us/variables/gov/states/mi/mdhhs/ssp/mi_ssp_living_arrangement.py
new file mode 100644
index 00000000000..5feae7dd471
--- /dev/null
+++ b/policyengine_us/variables/gov/states/mi/mdhhs/ssp/mi_ssp_living_arrangement.py
@@ -0,0 +1,26 @@
+from policyengine_us.model_api import *
+
+
+class MISSPLivingArrangement(Enum):
+    INDEPENDENT_LIVING = "Independent living"
+    HOUSEHOLD_OF_ANOTHER = "Household of another"
+    DOMICILIARY_CARE = "Adult foster care - domiciliary care"
+    PERSONAL_CARE = "Adult foster care - personal care"
+    HOME_FOR_AGED = "Home for the aged"
+    INSTITUTION = "Institution"
+    NONE = "Not in a qualifying arrangement"
+
+
+class mi_ssp_living_arrangement(Variable):
+    value_type = Enum
+    entity = Person
+    label = "Michigan SSP living arrangement"
+    definition_period = MONTH
+    defined_for = StateCode.MI
+    possible_values = MISSPLivingArrangement
+    default_value = MISSPLivingArrangement.INDEPENDENT_LIVING
+    reference = (
+        "https://mdhhs-pres-prod.michigan.gov/olmweb/EX/BP/Public/BEM/660.pdf#page=1",
+        "https://mdhhs-pres-prod.michigan.gov/olmweb/EX/BP/Public/BEM/660.pdf#page=4",
+        "https://mdhhs-pres-prod.michigan.gov/olmweb/ex/RF/Public/RFT/248.pdf#page=2",
+    )
diff --git a/policyengine_us/variables/gov/states/mi/mdhhs/ssp/mi_ssp_payment_category.py b/policyengine_us/variables/gov/states/mi/mdhhs/ssp/mi_ssp_payment_category.py
new file mode 100644
index 00000000000..308f6657188
--- /dev/null
+++ b/policyengine_us/variables/gov/states/mi/mdhhs/ssp/mi_ssp_payment_category.py
@@ -0,0 +1,43 @@
+from policyengine_us.model_api import *
+from policyengine_us.variables.gov.states.mi.mdhhs.ssp.mi_ssp_living_arrangement import (
+    MISSPLivingArrangement,
+)
+
+
+class mi_ssp_payment_category(Variable):
+    value_type = Enum
+    entity = Person
+    label = "Michigan SSP payment category"
+    definition_period = MONTH
+    defined_for = StateCode.MI
+    possible_values = MISSPLivingArrangement
+    default_value = MISSPLivingArrangement.INDEPENDENT_LIVING
+    reference = (
+        "https://mdhhs-pres-prod.michigan.gov/olmweb/EX/BP/Public/BEM/660.pdf#page=1",
+        "https://mdhhs-pres-prod.michigan.gov/olmweb/EX/BP/Public/BEM/660.pdf#page=4",
+        "https://mdhhs-pres-prod.michigan.gov/olmweb/ex/RF/Public/RFT/248.pdf#page=2",
+        "https://www.ecfr.gov/current/title-20/section-416.1131",
+    )
+
+    def formula(person, period, parameters):
+        # Federal living-arrangement codes (20 CFR 416.1131-1133, 416.414)
+        # override the manual input for the categories Michigan shares with
+        # federal SSI. Adult Foster Care and Home for the Aged categories
+        # are MI-specific and fall back to the user-provided input.
+        federal_arrangement = person("ssi_federal_living_arrangement", period.this_year)
+        federal_values = federal_arrangement.possible_values
+        in_medical_facility = (
+            federal_arrangement == federal_values.MEDICAL_TREATMENT_FACILITY
+        )
+        in_another_household = (
+            federal_arrangement == federal_values.ANOTHER_PERSONS_HOUSEHOLD
+        )
+        living_arrangement = person("mi_ssp_living_arrangement", period)
+        return select(
+            [in_medical_facility, in_another_household],
+            [
+                MISSPLivingArrangement.INSTITUTION,
+                MISSPLivingArrangement.HOUSEHOLD_OF_ANOTHER,
+            ],
+            default=living_arrangement,
+        )
diff --git a/policyengine_us/variables/gov/states/mi/mdhhs/ssp/mi_ssp_person.py b/policyengine_us/variables/gov/states/mi/mdhhs/ssp/mi_ssp_person.py
new file mode 100644
index 00000000000..a49362741ef
--- /dev/null
+++ b/policyengine_us/variables/gov/states/mi/mdhhs/ssp/mi_ssp_person.py
@@ -0,0 +1,35 @@
+from policyengine_us.model_api import *
+
+
+class mi_ssp_person(Variable):
+    value_type = float
+    entity = Person
+    label = "Michigan State Supplementary Payment per person"
+    unit = USD
+    definition_period = MONTH
+    defined_for = "mi_ssp_eligible"
+    reference = (
+        "https://mdhhs-pres-prod.michigan.gov/olmweb/EX/BP/Public/BEM/660.pdf#page=2",
+        "https://mdhhs-pres-prod.michigan.gov/olmweb/EX/BP/Public/BEM/660.pdf#page=4",
+        "https://mdhhs-pres-prod.michigan.gov/olmweb/ex/RF/Public/RFT/248.pdf#page=2",
+        "https://www.ssa.gov/policy/docs/progdesc/ssi_st_asst/2011/mi.html",
+    )
+
+    def formula(person, period, parameters):
+        couple_eligible = person("mi_ssp_couple_eligible", period)
+        base_amount = where(
+            couple_eligible,
+            person("mi_ssp_couple_amount", period),
+            person("mi_ssp_individual_amount", period),
+        )
+        # Per SSA 2011 baseline: countable income deducts from federal SSI
+        # first; any remaining countable income reduces the state
+        # supplement. uncapped_ssi = SSI amount if eligible − countable
+        # income; when countable exceeds the federal FBR, uncapped_ssi
+        # goes negative and that negative magnitude is the residual income
+        # to deduct from the SSP. uncapped_ssi has definition_period=YEAR
+        # but unit=USD, so the framework auto-divides by 12 when accessed
+        # from this MONTH formula via period.
+        uncapped_ssi = person("uncapped_ssi", period)
+        reduction = max_(0, -uncapped_ssi)
+        return max_(0, base_amount - reduction)
diff --git a/policyengine_us/variables/household/income/spm_unit/spm_unit_benefits.py b/policyengine_us/variables/household/income/spm_unit/spm_unit_benefits.py
index 9fdb27b3401..e59028de50b 100644
--- a/policyengine_us/variables/household/income/spm_unit/spm_unit_benefits.py
+++ b/policyengine_us/variables/household/income/spm_unit/spm_unit_benefits.py
@@ -24,6 +24,7 @@ def formula(spm_unit, period, parameters):
             "ks_sspp",  # Kansas benefits
             "hi_oss",
             "ma_state_supplement",  # Massachusetts benefits
+            "mi_ssp",  # Michigan benefits
             # California programs.
             "ca_cvrp",  # California Clean Vehicle Rebate Project.
             # Colorado programs.