diff --git a/changelog.d/sc-tanf-unearned-gross.fixed.md b/changelog.d/sc-tanf-unearned-gross.fixed.md
new file mode 100644
index 00000000000..f0683951987
--- /dev/null
+++ b/changelog.d/sc-tanf-unearned-gross.fixed.md
@@ -0,0 +1 @@
+South Carolina TANF now counts Social Security, unemployment compensation, pensions, retirement account withdrawals and interest at their gross amounts; adds child support, alimony, veterans benefits, workers' compensation, disability insurance, survivor and railroad retirement benefits, cash contributions, guaranteed income and trust income; counts capital gains, rent, partnership, trust and other net income only when positive, so a loss no longer offsets other income; drops discharged debt; treats farm income as earned; excludes the first $400 a year of a benefit group's interest and dividends; and leaves SSI recipients, their income and their resources out of the benefit group, as the TANF Policy Manual requires.
diff --git a/policyengine_us/parameters/gov/states/sc/tanf/income/earned/earned.yaml b/policyengine_us/parameters/gov/states/sc/tanf/income/earned/earned.yaml
index 02b09ea4d32..308693e947f 100644
--- a/policyengine_us/parameters/gov/states/sc/tanf/income/earned/earned.yaml
+++ b/policyengine_us/parameters/gov/states/sc/tanf/income/earned/earned.yaml
@@ -4,10 +4,11 @@ values:
     - employment_income_before_lsr
     - self_employment_income_before_lsr
     - sstb_self_employment_income_before_lsr
+    - farm_operations_income # Farm income is self-employment income
 metadata:
   unit: list
-  period: month 
-  label: South Carolina TANF earned income 
+  period: month
+  label: South Carolina TANF earned income
   reference:
-    - title: SC DSS TANF Policy Manual Section 7.1
-      href: https://dss.sc.gov/media/ojqddxsk/tanf-policy-manual-volume-65.pdf#page=101
+    - title: "SC DSS TANF Policy Manual (Volume 67), Sections 7.1 and 7.7 #page 102,112"
+      href: https://dss.sc.gov/media/bxwc1jdj/tanf-policy-manual-volume-67-final.pdf#page=102
diff --git a/policyengine_us/parameters/gov/states/sc/tanf/income/unearned.yaml b/policyengine_us/parameters/gov/states/sc/tanf/income/unearned.yaml
deleted file mode 100644
index 247415c9c25..00000000000
--- a/policyengine_us/parameters/gov/states/sc/tanf/income/unearned.yaml
+++ /dev/null
@@ -1,28 +0,0 @@
-description: South Carolina counts these income sources as unearned income under the Temporary Assistance for Needy Families program.
-values:
-  1996-07-01:
-    - partnership_s_corp_income
-    - farm_operations_income
-    - farm_rent_income
-    - capital_gains
-    - taxable_interest_income
-    - rental_income
-    # Royalties included in rental income
-    - dividend_income
-    - taxable_pension_income 
-    # Pension income includes annuities and endowment contracts
-    - debt_relief
-    # Decedent income
-    # Estate interest income
-    - taxable_unemployment_compensation
-    - taxable_social_security
-    - illicit_income
-    - taxable_retirement_distributions
-    - miscellaneous_income
-metadata:
-  unit: list
-  period: month 
-  label: South Carolina TANF unearned income 
-  reference:
-    - title: SC DSS TANF Policy Manual Section 7.1
-      href: https://dss.sc.gov/media/ojqddxsk/tanf-policy-manual-volume-65.pdf#page=101
diff --git a/policyengine_us/parameters/gov/states/sc/tanf/income/unearned/interest_and_dividends/exclusion.yaml b/policyengine_us/parameters/gov/states/sc/tanf/income/unearned/interest_and_dividends/exclusion.yaml
new file mode 100644
index 00000000000..75e3c54d269
--- /dev/null
+++ b/policyengine_us/parameters/gov/states/sc/tanf/income/unearned/interest_and_dividends/exclusion.yaml
@@ -0,0 +1,11 @@
+description: South Carolina excludes this amount of interest, dividends and royalties per benefit group each year under the Temporary Assistance for Needy Families program.
+values:
+  1996-07-01: 400
+
+metadata:
+  unit: currency-USD
+  period: year
+  label: South Carolina TANF interest and dividend exclusion
+  reference:
+    - title: SC DSS TANF Policy Manual (Volume 67), Section 7.7
+      href: https://dss.sc.gov/media/bxwc1jdj/tanf-policy-manual-volume-67-final.pdf#page=113
diff --git a/policyengine_us/parameters/gov/states/sc/tanf/income/unearned/interest_and_dividends/sources.yaml b/policyengine_us/parameters/gov/states/sc/tanf/income/unearned/interest_and_dividends/sources.yaml
new file mode 100644
index 00000000000..3a5de9446f7
--- /dev/null
+++ b/policyengine_us/parameters/gov/states/sc/tanf/income/unearned/interest_and_dividends/sources.yaml
@@ -0,0 +1,14 @@
+description: South Carolina counts these income sources as unearned income after the interest, dividend and royalty exclusion under the Temporary Assistance for Needy Families program.
+values:
+  1996-07-01:
+    - interest_income
+    - dividend_income
+    # Royalties are included in rental income, which has no separate
+    # royalty input, so they are counted without this exclusion.
+metadata:
+  unit: list
+  period: year
+  label: South Carolina TANF interest and dividend sources
+  reference:
+    - title: SC DSS TANF Policy Manual (Volume 67), Section 7.7
+      href: https://dss.sc.gov/media/bxwc1jdj/tanf-policy-manual-volume-67-final.pdf#page=113
diff --git a/policyengine_us/parameters/gov/states/sc/tanf/income/unearned/positive_sources.yaml b/policyengine_us/parameters/gov/states/sc/tanf/income/unearned/positive_sources.yaml
new file mode 100644
index 00000000000..b5de332b214
--- /dev/null
+++ b/policyengine_us/parameters/gov/states/sc/tanf/income/unearned/positive_sources.yaml
@@ -0,0 +1,19 @@
+description: South Carolina counts the positive amount of each of these income sources as unearned income under the Temporary Assistance for Needy Families program.
+values:
+  1996-07-01:
+    # These are net amounts that can be losses. Income is money received
+    # (Section 7.1), so a net loss counts as zero rather than offsetting other
+    # income; Section 8.16 allows no deduction for one.
+    - capital_gains # Capital gains (other)
+    - rental_income # Rent payments, after the cost of doing business; includes royalties
+    - farm_rent_income
+    - partnership_s_corp_income
+    - estate_income # Trust and estate income; estate settlements are resources (Section 6.6)
+    - miscellaneous_income
+metadata:
+  unit: list
+  period: month
+  label: South Carolina TANF unearned income sources counted when positive
+  reference:
+    - title: "SC DSS TANF Policy Manual (Volume 67), Sections 6.6, 7.1, 7.7 and 8.16 #page 92,102,108,116,134"
+      href: https://dss.sc.gov/media/bxwc1jdj/tanf-policy-manual-volume-67-final.pdf#page=92
diff --git a/policyengine_us/parameters/gov/states/sc/tanf/income/unearned/sources.yaml b/policyengine_us/parameters/gov/states/sc/tanf/income/unearned/sources.yaml
new file mode 100644
index 00000000000..17c0fd64194
--- /dev/null
+++ b/policyengine_us/parameters/gov/states/sc/tanf/income/unearned/sources.yaml
@@ -0,0 +1,31 @@
+description: South Carolina counts these income sources, along with interest and dividends, as unearned income under the Temporary Assistance for Needy Families program.
+values:
+  1996-07-01:
+    # Section 7.1 defines income as money received from any source, and the
+    # Section 7.7 chart counts each source below at its gross amount.
+    # Interest and dividends are counted separately, after the $400
+    # exclusion (see interest_and_dividends), and net amounts that can be
+    # losses only when positive (see positive_sources).
+    - social_security # SSA benefits: count the gross amount
+    - total_unemployment_compensation # Reported, or modeled state UI
+    - pension_income # Pension; annuities and endowment contracts
+    - retirement_distributions # IRA and 401(k) withdrawals: money received
+    - railroad_benefits # Retirement Pay (Railroad Retirement)
+    - survivor_benefits # Pension and retirement pay to survivors
+    - veterans_benefits
+    - workers_compensation
+    - disability_benefits # Income maintenance insurance, including disability insurance
+    - child_support_received # Child support/direct
+    - alimony_income
+    - financial_assistance # Cash contributions
+    - gi_cash_assistance
+    - illicit_income
+    # Not listed: farm operations income is earned self-employment income
+    # (Section 7.7), and discharged debt is not money received (Section 7.1).
+metadata:
+  unit: list
+  period: month
+  label: South Carolina TANF unearned income sources
+  reference:
+    - title: "SC DSS TANF Policy Manual (Volume 67), Sections 7.1 and 7.7 #page 102,107-120"
+      href: https://dss.sc.gov/media/bxwc1jdj/tanf-policy-manual-volume-67-final.pdf#page=102
diff --git a/policyengine_us/tests/policy/baseline/gov/states/sc/tanf/integration.yaml b/policyengine_us/tests/policy/baseline/gov/states/sc/tanf/integration.yaml
index 41aecd45e29..132ca63c7e7 100644
--- a/policyengine_us/tests/policy/baseline/gov/states/sc/tanf/integration.yaml
+++ b/policyengine_us/tests/policy/baseline/gov/states/sc/tanf/integration.yaml
@@ -24,7 +24,7 @@
     sc_tanf: 435.28
     # tanf_fpg for size 3 (2025-01, uses 2024-10 FPG) = 2151.67/month
     # need_standard = 2151.67 * 0.5 = 1075.83
-    # benefit = 1075.83 * 0.4046 = 435.49
+    # benefit = 1075.83 * 0.4046 = 435.28
 
 - name: Case 2, single parent with earned income.
   absolute_error_margin: 0.1
@@ -115,7 +115,7 @@
       person1:
         age: 35
         employment_income_before_lsr: 0
-        taxable_social_security: 3_600
+        social_security_disability: 3_600
       person2:
         age: 8
         is_child_dependent: true
@@ -129,6 +129,7 @@
         state_code: SC
   output:
     sc_tanf: 223.20
+    # SSA benefits count at the gross amount (Section 7.7, page 116)
     # monthly unearned = 3,600/12 = 300
     # tanf_fpg for size 2 = 1703.33
     # need_standard = 1703.33 * 0.5 = 851.67
@@ -222,3 +223,134 @@
     sc_tanf: 0
     # Both members are undocumented, so no one qualifies as
     # citizen or legal immigrant -> ineligible
+
+- name: Case 9, child support, a child's Social Security and interest above the exclusion.
+  period: 2025-01
+  absolute_error_margin: 0.1
+  input:
+    people:
+      person1:
+        age: 30
+        employment_income_before_lsr: 0
+        child_support_received: 3_600
+        taxable_interest_income: 1_000
+      person2:
+        age: 9
+        is_child_dependent: true
+        social_security_survivors: 4_800
+      person3:
+        age: 6
+        is_child_dependent: true
+    spm_units:
+      spm_unit:
+        members: [person1, person2, person3]
+        spm_unit_cash_assets: 500
+    households:
+      household:
+        members: [person1, person2, person3]
+        state_code: SC
+  output:
+    sc_tanf_gross_income: 750
+    sc_tanf: 131.83
+    # SC DSS TANF Policy Manual (Volume 67), Section 7.7:
+    # child support paid directly = 3,600/12 = 300 (page 108)
+    # child's SSA benefits, gross = 4,800/12 = 400 (page 116)
+    # interest = (1,000 - 400 exclusion)/12 = 50 (page 113)
+    # gross income = 300 + 400 + 50 = 750
+    # tanf_fpg for size 3 = 2151.67; need standard = 1075.83
+    # gross income limit = 1075.83 * 1.85 = 1990.29; 750 passes
+    # benefit = (1075.83 - 750) * 0.4046 = 131.83
+
+- name: Case 10, an SSI child and the child's income are excluded from the benefit group.
+  period: 2025-01
+  absolute_error_margin: 0.1
+  input:
+    people:
+      person1:
+        age: 30
+        employment_income_before_lsr: 0
+      person2:
+        age: 9
+        is_child_dependent: true
+        receives_ssi: true
+        taxable_private_pension_income: 3_600
+      person3:
+        age: 6
+        is_child_dependent: true
+    spm_units:
+      spm_unit:
+        members: [person1, person2, person3]
+        spm_unit_cash_assets: 500
+    households:
+      household:
+        members: [person1, person2, person3]
+        state_code: SC
+  output:
+    sc_tanf_benefit_group_size: 2
+    sc_tanf_gross_income: 0
+    sc_tanf_need_standard: 851.67
+    sc_tanf: 344.58
+    # SC DSS TANF Policy Manual (Volume 67), Section 3.6 (page 56) and
+    # Section 7.7 (page 117): exclude the SSI recipient, his/her income and
+    # resources. The benefit group is the parent and the other child.
+    # FPG for 2 = 1703.33; need standard = 851.67
+    # benefit = 851.67 * 0.4046 = 344.58
+
+- name: Case 11, when the only child receives SSI, the parent is the only benefit group member.
+  period: 2025-01
+  absolute_error_margin: 0.1
+  input:
+    people:
+      person1:
+        age: 30
+        employment_income_before_lsr: 0
+      person2:
+        age: 9
+        is_child_dependent: true
+        receives_ssi: true
+    spm_units:
+      spm_unit:
+        members: [person1, person2]
+        spm_unit_cash_assets: 500
+    households:
+      household:
+        members: [person1, person2]
+        state_code: SC
+  output:
+    sc_tanf_benefit_group_size: 1
+    sc_tanf: 253.89
+    # Section 3.6 (page 56): "If an SSI child is the only child in the home,
+    # include the parent(s) as the only BG member."
+    # FPG for 1 = 1255; need standard = 627.50
+    # benefit = 627.50 * 0.4046 = 253.89
+
+- name: Case 12, an SSI child's savings do not count against the resource limit.
+  period: 2025-01
+  absolute_error_margin: 0.1
+  input:
+    people:
+      person1:
+        age: 30
+        employment_income_before_lsr: 0
+        bank_account_assets: 800
+      person2:
+        age: 9
+        is_child_dependent: true
+        receives_ssi: true
+        bank_account_assets: 1_800
+      person3:
+        age: 6
+        is_child_dependent: true
+    spm_units:
+      spm_unit:
+        members: [person1, person2, person3]
+    households:
+      household:
+        members: [person1, person2, person3]
+        state_code: SC
+  output:
+    sc_tanf_countable_resources: 800
+    sc_tanf: 344.58
+    # Sections 3.6 (page 56) and 7.7 (page 117) exclude the SSI child's
+    # resources: 2,600 - 1,800 = 800, within the $2,500 limit (page 91).
+    # Benefit group of 2: need standard 851.67; benefit = 851.67 * 0.4046
diff --git a/policyengine_us/tests/policy/baseline/gov/states/sc/tanf/sc_tanf.yaml b/policyengine_us/tests/policy/baseline/gov/states/sc/tanf/sc_tanf.yaml
index 01f7c7cfc9a..b8b094df985 100644
--- a/policyengine_us/tests/policy/baseline/gov/states/sc/tanf/sc_tanf.yaml
+++ b/policyengine_us/tests/policy/baseline/gov/states/sc/tanf/sc_tanf.yaml
@@ -5,10 +5,10 @@
     state_code: SC
     sc_tanf_countable_income: 0
     sc_tanf_eligible: true
-    spm_unit_size: 2
+    sc_tanf_benefit_group_size: 2
   output:
     sc_tanf: 344.58
-    # tanf_fpg for size 2 (2025-01, uses 2024-10 FPG) = 1703.33/month
+    # FPG for a benefit group of 2 (2025-01, uses 2024-10 FPG) = 1703.33/month
     # need_standard = 1703.33 * 0.5 = 851.67
     # benefit = 851.67 * 0.4046 = 344.59
 
@@ -18,7 +18,7 @@
     state_code: SC
     sc_tanf_countable_income: 1_000
     sc_tanf_eligible: false
-    spm_unit_size: 2
+    sc_tanf_benefit_group_size: 2
   output:
     sc_tanf: 0
 
@@ -29,10 +29,10 @@
     state_code: SC
     sc_tanf_countable_income: 500
     sc_tanf_eligible: true
-    spm_unit_size: 2
+    sc_tanf_benefit_group_size: 2
   output:
     sc_tanf: 142.28
-    # tanf_fpg for size 2 (2025-01) = 1703.33/month
+    # FPG for a benefit group of 2 (2025-01) = 1703.33/month
     # need_standard = 1703.33 * 0.5 = 851.67
     # excess = 851.67 - 500 = 351.67
     # benefit = 351.67 * 0.4046 = 142.31
diff --git a/policyengine_us/tests/policy/baseline/gov/states/sc/tanf/sc_tanf_benefit_group_size.yaml b/policyengine_us/tests/policy/baseline/gov/states/sc/tanf/sc_tanf_benefit_group_size.yaml
new file mode 100644
index 00000000000..3153dc06e45
--- /dev/null
+++ b/policyengine_us/tests/policy/baseline/gov/states/sc/tanf/sc_tanf_benefit_group_size.yaml
@@ -0,0 +1,63 @@
+# SC DSS TANF Policy Manual (Volume 67), Section 3.6 (page 56) and Section 7.7
+# (page 117): exclude an SSI recipient living with the benefit group.
+
+- name: Case 1, everyone in the unit is in the benefit group.
+  period: 2025-01
+  input:
+    people:
+      person1:
+        age: 30
+      person2:
+        age: 9
+      person3:
+        age: 6
+    spm_units:
+      spm_unit:
+        members: [person1, person2, person3]
+    households:
+      household:
+        members: [person1, person2, person3]
+        state_code: SC
+  output:
+    sc_tanf_benefit_group_size: 3
+
+- name: Case 2, an SSI recipient is left out.
+  period: 2025-01
+  input:
+    people:
+      person1:
+        age: 30
+      person2:
+        age: 9
+        receives_ssi: true
+      person3:
+        age: 6
+    spm_units:
+      spm_unit:
+        members: [person1, person2, person3]
+    households:
+      household:
+        members: [person1, person2, person3]
+        state_code: SC
+  output:
+    sc_tanf_benefit_group_size: 2
+
+- name: Case 3, a unit of SSI recipients has no benefit group members.
+  period: 2025-01
+  input:
+    people:
+      person1:
+        age: 30
+        receives_ssi: true
+      person2:
+        age: 9
+        receives_ssi: true
+    spm_units:
+      spm_unit:
+        members: [person1, person2]
+    households:
+      household:
+        members: [person1, person2]
+        state_code: SC
+  output:
+    sc_tanf_benefit_group_size: 0
diff --git a/policyengine_us/tests/policy/baseline/gov/states/sc/tanf/sc_tanf_countable_income_eligible.yaml b/policyengine_us/tests/policy/baseline/gov/states/sc/tanf/sc_tanf_countable_income_eligible.yaml
index ed35d4779a1..624cdcf1949 100644
--- a/policyengine_us/tests/policy/baseline/gov/states/sc/tanf/sc_tanf_countable_income_eligible.yaml
+++ b/policyengine_us/tests/policy/baseline/gov/states/sc/tanf/sc_tanf_countable_income_eligible.yaml
@@ -2,7 +2,7 @@
   period: 2025-01
   input:
     state_code: SC
-    spm_unit_size: 2
+    sc_tanf_benefit_group_size: 2
   output:
     sc_tanf_countable_income_eligible: true
 
@@ -10,11 +10,11 @@
   period: 2025-01
   input:
     state_code: SC
-    spm_unit_size: 2
+    sc_tanf_benefit_group_size: 2
     sc_tanf_countable_income: 800
   output:
     sc_tanf_countable_income_eligible: true
-    # tanf_fpg for size 2 (2025-01) = 1703.33/month
+    # FPG for a benefit group of 2 (2025-01) = 1703.33/month
     # need_standard = 1703.33 * 0.5 = 851.67
     # 800 < 851.67 -> eligible
 
@@ -22,7 +22,7 @@
   period: 2025-01
   input:
     state_code: SC
-    spm_unit_size: 2
+    sc_tanf_benefit_group_size: 2
     sc_tanf_countable_income: 900
   output:
     sc_tanf_countable_income_eligible: false
@@ -34,11 +34,11 @@
   absolute_error_margin: 0.1
   input:
     state_code: SC
-    spm_unit_size: 2
+    sc_tanf_benefit_group_size: 2
     sc_tanf_countable_income: 851.67
   output:
     sc_tanf_countable_income_eligible: false
-    # tanf_fpg for size 2 = 1703.33
+    # FPG for a benefit group of 2 = 1703.33
     # need_standard = 1703.33 * 0.5 = 851.67
     # 851.67 < 851.67 is FALSE (strict less than)
     # -> not eligible
diff --git a/policyengine_us/tests/policy/baseline/gov/states/sc/tanf/sc_tanf_countable_resources.yaml b/policyengine_us/tests/policy/baseline/gov/states/sc/tanf/sc_tanf_countable_resources.yaml
new file mode 100644
index 00000000000..d94d83f5f8a
--- /dev/null
+++ b/policyengine_us/tests/policy/baseline/gov/states/sc/tanf/sc_tanf_countable_resources.yaml
@@ -0,0 +1,60 @@
+# SC DSS TANF Policy Manual (Volume 67), Sections 3.6 (page 56) and 7.7
+# (page 117): exclude the SSI recipient's resources; Section 6.4 (page 91):
+# $2,500 limit per benefit group.
+
+- name: Case 1, an SSI recipient's own assets are left out.
+  period: 2025-01
+  input:
+    people:
+      person1:
+        age: 30
+        bank_account_assets: 800
+      person2:
+        age: 9
+        receives_ssi: true
+        bank_account_assets: 1_800
+    spm_units:
+      spm_unit:
+        members: [person1, person2]
+    households:
+      household:
+        members: [person1, person2]
+        state_code: SC
+  output:
+    # 2,600 in the unit, less the SSI child's 1,800.
+    sc_tanf_countable_resources: 800
+    sc_tanf_resources_eligible: true
+
+- name: Case 2, stocks and bonds of an SSI recipient are left out too.
+  period: 2025-01
+  input:
+    people:
+      person1:
+        age: 30
+        bank_account_assets: 500
+        stock_assets: 1_000
+      person2:
+        age: 40
+        receives_ssi: true
+        stock_assets: 2_000
+        bond_assets: 1_000
+    spm_units:
+      spm_unit:
+        members: [person1, person2]
+    households:
+      household:
+        members: [person1, person2]
+        state_code: SC
+  output:
+    sc_tanf_countable_resources: 1_500
+
+- name: Case 3, an aggregate asset input is counted as given.
+  period: 2025-01
+  input:
+    state_code: SC
+    receives_ssi: true
+    spm_unit_cash_assets: 3_000
+  output:
+    # Without person-level assets nothing can be attributed to the SSI
+    # recipient, so the aggregate stands.
+    sc_tanf_countable_resources: 3_000
diff --git a/policyengine_us/tests/policy/baseline/gov/states/sc/tanf/sc_tanf_gross_earned_income.yaml b/policyengine_us/tests/policy/baseline/gov/states/sc/tanf/sc_tanf_gross_earned_income.yaml
new file mode 100644
index 00000000000..e2fb138f4e1
--- /dev/null
+++ b/policyengine_us/tests/policy/baseline/gov/states/sc/tanf/sc_tanf_gross_earned_income.yaml
@@ -0,0 +1,23 @@
+# SC DSS TANF Policy Manual (Volume 67), Sections 7.1 and 7.7.
+
+- name: Case 1, wages and farm income are earned income.
+  period: 2025-01
+  absolute_error_margin: 0.01
+  input:
+    state_code: SC
+    employment_income_before_lsr: 12_000
+    farm_operations_income: 2_400
+  output:
+    # Wages (page 102) and farm income (self-employment, page 112) are earned.
+    # (12,000 + 2,400) / 12 = 1,200.
+    sc_tanf_gross_earned_income: 1_200
+
+- name: Case 2, an SSI recipient's earnings are excluded.
+  period: 2025-01
+  input:
+    state_code: SC
+    receives_ssi: true
+    employment_income_before_lsr: 6_000
+  output:
+    # SSI benefit: exclude the SSI recipient and his or her income (page 117).
+    sc_tanf_gross_earned_income: 0
diff --git a/policyengine_us/tests/policy/baseline/gov/states/sc/tanf/sc_tanf_gross_income_eligible.yaml b/policyengine_us/tests/policy/baseline/gov/states/sc/tanf/sc_tanf_gross_income_eligible.yaml
index dd0656ebf42..4e3c80b52bd 100644
--- a/policyengine_us/tests/policy/baseline/gov/states/sc/tanf/sc_tanf_gross_income_eligible.yaml
+++ b/policyengine_us/tests/policy/baseline/gov/states/sc/tanf/sc_tanf_gross_income_eligible.yaml
@@ -2,7 +2,7 @@
   period: 2025-01
   input:
     state_code: SC
-    spm_unit_size: 2
+    sc_tanf_benefit_group_size: 2
   output:
     sc_tanf_gross_income_eligible: true
 
@@ -10,12 +10,12 @@
   period: 2025-01
   input:
     state_code: SC
-    spm_unit_size: 2
+    sc_tanf_benefit_group_size: 2
     employment_income_before_lsr: 18_000
   output:
     sc_tanf_gross_income_eligible: true
     # monthly earned = 18,000 / 12 = 1,500
-    # tanf_fpg for size 2 (2025-01) = 1703.33/month
+    # FPG for a benefit group of 2 (2025-01) = 1703.33/month
     # need_standard = 1703.33 * 0.5 = 851.67
     # gross_income_limit = 851.67 * 1.85 = 1575.58
     # 1,500 <= 1,575.58 -> eligible
@@ -24,7 +24,7 @@
   period: 2025-01
   input:
     state_code: SC
-    spm_unit_size: 2
+    sc_tanf_benefit_group_size: 2
     employment_income_before_lsr: 24_000
   output:
     sc_tanf_gross_income_eligible: false
@@ -37,11 +37,11 @@
   absolute_error_margin: 0.1
   input:
     state_code: SC
-    spm_unit_size: 2
+    sc_tanf_benefit_group_size: 2
     sc_tanf_gross_income: 1_575.58
   output:
     sc_tanf_gross_income_eligible: true
-    # tanf_fpg for size 2 = 1703.33
+    # FPG for a benefit group of 2 = 1703.33
     # need_standard = 1703.33 * 0.5 = 851.665
     # gross_income_limit = 851.665 * 1.85 = 1575.58
     # 1575.58 <= 1575.58 -> eligible (uses <=)
diff --git a/policyengine_us/tests/policy/baseline/gov/states/sc/tanf/sc_tanf_gross_unearned_income.yaml b/policyengine_us/tests/policy/baseline/gov/states/sc/tanf/sc_tanf_gross_unearned_income.yaml
new file mode 100644
index 00000000000..c9fece1b5b0
--- /dev/null
+++ b/policyengine_us/tests/policy/baseline/gov/states/sc/tanf/sc_tanf_gross_unearned_income.yaml
@@ -0,0 +1,283 @@
+# SC DSS TANF Policy Manual (Volume 67), Section 7.1 (page 102) defines income
+# as money received from any source; the Section 7.7 chart (pages 107-120)
+# lists how each source is counted.
+
+- name: Case 1, Social Security counts at the gross amount, not the taxable part.
+  period: 2025-01
+  absolute_error_margin: 0.01
+  input:
+    state_code: SC
+    social_security_retirement: 6_000
+  output:
+    # SSA benefits: "Count gross amount" (page 116).
+    # 6,000 / 12 = 500. The federally taxable part is 0 at this income.
+    taxable_social_security: 0
+    sc_tanf_gross_unearned_income: 500
+
+- name: Case 2, 2020 unemployment compensation counts in full despite the IRC 85(c) exclusion.
+  period: 2020-01
+  absolute_error_margin: 0.01
+  input:
+    state_code: SC
+    unemployment_compensation: 12_000
+  output:
+    # Unemployment compensation benefits are counted (page 118).
+    # 12,000 / 12 = 1,000. Federal law excluded $10,200 for 2020, so the
+    # taxable part was 1,800 a year (150 a month); TANF counts all 1,000.
+    sc_tanf_gross_unearned_income: 1_000
+
+- name: Case 3, taxable and tax-exempt pension income both count.
+  period: 2025-01
+  absolute_error_margin: 0.01
+  input:
+    state_code: SC
+    taxable_private_pension_income: 2_400
+    tax_exempt_private_pension_income: 1_200
+  output:
+    # Pension and retirement pay are counted (pages 115-116).
+    # (2,400 + 1,200) / 12 = 300.
+    sc_tanf_gross_unearned_income: 300
+
+- name: Case 4, non-taxable cash income the chart counts.
+  period: 2025-01
+  absolute_error_margin: 0.01
+  input:
+    state_code: SC
+    child_support_received: 1_200
+    alimony_income: 1_200
+    veterans_benefits: 1_200
+    workers_compensation: 1_200
+    disability_benefits: 1_200
+    survivor_benefits: 1_200
+    railroad_benefits: 1_200
+    financial_assistance: 1_200
+    gi_cash_assistance: 1_200
+    estate_income: 1_200
+  output:
+    # Child support/direct, alimony, cash contributions (page 108), income
+    # maintenance insurance including disability insurance (page 113),
+    # retirement pay including railroad retirement (page 116), VA benefits
+    # (page 119) and workers' compensation (page 120) are counted, as are
+    # guaranteed income payments and trust income, which are money received
+    # (Section 7.1, page 102).
+    # 10 sources x 1,200 / 12 = 1,000.
+    sc_tanf_gross_unearned_income: 1_000
+
+- name: Case 5, retirement account withdrawals count at the gross amount and discharged debt does not.
+  period: 2025-01
+  absolute_error_margin: 0.01
+  input:
+    state_code: SC
+    taxable_ira_distributions: 9_600
+    taxable_401k_distributions: 2_400
+    debt_relief: 6_000
+  output:
+    # Withdrawals are money received (Section 7.1, page 102). A discharged
+    # debt is not money received, and in-kind gains are excluded.
+    # (9,600 + 2,400) / 12 = 1,000.
+    sc_tanf_gross_unearned_income: 1_000
+
+- name: Case 6, farm operations income is earned, not unearned.
+  period: 2025-01
+  input:
+    state_code: SC
+    farm_operations_income: 6_000
+  output:
+    # Farm income is self-employment income (page 112).
+    sc_tanf_gross_unearned_income: 0
+    sc_tanf_gross_earned_income: 500
+
+- name: Case 7, interest within the 400 dollar annual exclusion is not counted.
+  period: 2025-01
+  input:
+    state_code: SC
+    taxable_interest_income: 300
+  output:
+    # Up to $400 per benefit group annually is excluded (page 113).
+    # 300 / 12 = 25 a month, below the 400 / 12 = 33.33 monthly exclusion.
+    sc_tanf_gross_unearned_income: 0
+
+- name: Case 8, interest above the exclusion is averaged over 12 months, including tax-exempt interest.
+  period: 2025-01
+  absolute_error_margin: 0.01
+  input:
+    state_code: SC
+    taxable_interest_income: 600
+    tax_exempt_interest_income: 1_000
+  output:
+    # Interest is money received whether or not it is taxable.
+    # (600 + 1,000 - 400) / 12 = 100.
+    sc_tanf_gross_unearned_income: 100
+
+- name: Case 9, the exclusion is shared across the benefit group in proportion to each member's interest and dividends.
+  period: 2025-01
+  absolute_error_margin: 0.01
+  input:
+    people:
+      person1:
+        age: 35
+        taxable_interest_income: 600
+      person2:
+        age: 10
+        qualified_dividend_income: 600
+    spm_units:
+      spm_unit:
+        members: [person1, person2]
+    households:
+      household:
+        members: [person1, person2]
+        state_code: SC
+  output:
+    # Each member has 600 / 12 = 50 a month; the group has 100.
+    # Group exclusion = min(100, 400 / 12 = 33.33) = 33.33, half to each.
+    # Each member: 50 - 16.67 = 33.33. Group total = (1,200 - 400) / 12 = 66.67.
+    sc_tanf_gross_unearned_income: [33.33, 33.33]
+
+- name: Case 10, an SSI recipient's income is excluded.
+  period: 2025-01
+  input:
+    state_code: SC
+    receives_ssi: true
+    social_security_disability: 4_800
+    taxable_interest_income: 1_200
+  output:
+    # SSI benefit: exclude the SSI recipient and his or her income (page 117).
+    sc_tanf_ssi_recipient: true
+    sc_tanf_gross_unearned_income: 0
+
+- name: Case 11, an SSI recipient's interest does not use up the group's exclusion.
+  period: 2025-01
+  absolute_error_margin: 0.01
+  input:
+    people:
+      person1:
+        age: 35
+        taxable_interest_income: 600
+      person2:
+        age: 60
+        receives_ssi: true
+        taxable_interest_income: 1_200
+    spm_units:
+      spm_unit:
+        members: [person1, person2]
+    households:
+      household:
+        members: [person1, person2]
+        state_code: SC
+  output:
+    # Only person1's income counts: 600 / 12 = 50, less the full 33.33
+    # exclusion = 16.67. Person2's income is excluded.
+    sc_tanf_gross_unearned_income: [16.67, 0]
+
+- name: Case 12, negative interest does not offset other income.
+  period: 2025-01
+  absolute_error_margin: 0.01
+  input:
+    state_code: SC
+    taxable_interest_income: -1_200
+    taxable_private_pension_income: 2_400
+  output:
+    # Interest and dividends count only as money received, floored at zero,
+    # before the exclusion. Pension 2,400 / 12 = 200.
+    sc_tanf_gross_unearned_income: 200
+
+- name: Case 13, one member's negative interest does not reduce another member's.
+  period: 2025-01
+  absolute_error_margin: 0.01
+  input:
+    people:
+      person1:
+        age: 35
+        taxable_interest_income: 600
+      person2:
+        age: 10
+        taxable_interest_income: -600
+    spm_units:
+      spm_unit:
+        members: [person1, person2]
+    households:
+      household:
+        members: [person1, person2]
+        state_code: SC
+  output:
+    # Person1: 600 / 12 = 50, less the 33.33 exclusion = 16.67. Person2: 0.
+    sc_tanf_gross_unearned_income: [16.67, 0]
+
+- name: Case 14, dividends entered as the legacy dividend_income input count.
+  period: 2025-01
+  absolute_error_margin: 0.01
+  input:
+    state_code: SC
+    dividend_income: 1_200
+  output:
+    # (1,200 - 400) / 12 = 66.67.
+    sc_tanf_gross_unearned_income: 66.67
+
+- name: Case 15, a trust or estate loss does not offset other income.
+  period: 2025-01
+  absolute_error_margin: 0.01
+  input:
+    state_code: SC
+    estate_income: -1_200
+    taxable_private_pension_income: 2_400
+  output:
+    # A pass-through loss is not money received (Section 7.1, page 102).
+    # Pension 2,400 / 12 = 200.
+    sc_tanf_gross_unearned_income: 200
+
+- name: Case 16, one member's estate loss does not offset another member's income.
+  period: 2025-01
+  absolute_error_margin: 0.01
+  input:
+    people:
+      person1:
+        age: 35
+        taxable_private_pension_income: 2_400
+      person2:
+        age: 10
+        estate_income: -1_200
+    spm_units:
+      spm_unit:
+        members: [person1, person2]
+    households:
+      household:
+        members: [person1, person2]
+        state_code: SC
+  output:
+    sc_tanf_gross_unearned_income: [200, 0]
+
+- name: Case 17, one member's partnership loss does not offset another member's pension.
+  period: 2025-01
+  absolute_error_margin: 0.01
+  input:
+    people:
+      person1:
+        age: 35
+        taxable_private_pension_income: 2_400
+      person2:
+        age: 10
+        partnership_income: -1_200
+    spm_units:
+      spm_unit:
+        members: [person1, person2]
+    households:
+      household:
+        members: [person1, person2]
+        state_code: SC
+  output:
+    # A net loss is not money received (Section 7.1, page 102).
+    sc_tanf_gross_unearned_income: [200, 0]
+
+- name: Case 18, capital and rental losses do not offset the same member's income.
+  period: 2025-01
+  absolute_error_margin: 0.01
+  input:
+    state_code: SC
+    short_term_capital_gains: -3_000
+    rental_income: -2_400
+    farm_rent_income: 1_200
+    taxable_private_pension_income: 2_400
+  output:
+    # Each net source is floored at zero on its own: farm rent 1,200 / 12 =
+    # 100 plus pension 2,400 / 12 = 200.
+    sc_tanf_gross_unearned_income: 300
diff --git a/policyengine_us/tests/policy/baseline/gov/states/sc/tanf/sc_tanf_income_eligible.yaml b/policyengine_us/tests/policy/baseline/gov/states/sc/tanf/sc_tanf_income_eligible.yaml
index da84d0c22da..cbeec5cd65a 100644
--- a/policyengine_us/tests/policy/baseline/gov/states/sc/tanf/sc_tanf_income_eligible.yaml
+++ b/policyengine_us/tests/policy/baseline/gov/states/sc/tanf/sc_tanf_income_eligible.yaml
@@ -4,7 +4,7 @@
     state_code: SC
     sc_tanf_countable_income: 0
     sc_tanf_gross_income: 0
-    spm_unit_size: 2
+    sc_tanf_benefit_group_size: 2
   output:
     sc_tanf_income_eligible: true
 
@@ -14,10 +14,10 @@
     state_code: SC
     sc_tanf_countable_income: 500
     sc_tanf_gross_income: 2_000
-    spm_unit_size: 2
+    sc_tanf_benefit_group_size: 2
   output:
     sc_tanf_income_eligible: false
-    # tanf_fpg for size 2 (2025-01) = 1703.33/month
+    # FPG for a benefit group of 2 (2025-01) = 1703.33/month
     # need_standard = 1703.33 * 0.5 = 851.67
     # gross_income_limit = 851.67 * 1.85 = 1575.58
     # gross_income 2,000 > 1,575.58 -> not eligible
@@ -28,7 +28,7 @@
     state_code: SC
     sc_tanf_countable_income: 900
     sc_tanf_gross_income: 1_200
-    spm_unit_size: 2
+    sc_tanf_benefit_group_size: 2
   output:
     sc_tanf_income_eligible: false
     # need_standard = 851.67
@@ -42,7 +42,7 @@
     state_code: SC
     sc_tanf_countable_income: 800
     sc_tanf_gross_income: 1_000
-    spm_unit_size: 2
+    sc_tanf_benefit_group_size: 2
   output:
     sc_tanf_income_eligible: true
     # gross 1,000 < 1,575.58 -> passes gross test
diff --git a/policyengine_us/tests/policy/baseline/gov/states/sc/tanf/sc_tanf_need_standard.yaml b/policyengine_us/tests/policy/baseline/gov/states/sc/tanf/sc_tanf_need_standard.yaml
new file mode 100644
index 00000000000..31ab0230586
--- /dev/null
+++ b/policyengine_us/tests/policy/baseline/gov/states/sc/tanf/sc_tanf_need_standard.yaml
@@ -0,0 +1,32 @@
+# SC DSS TANF Policy Manual (Volume 67), Section 8.15 (page 133): the need
+# standard is 50% of the federal poverty guideline for the number of persons
+# in the benefit group, revised each October 1.
+
+- name: Case 1, benefit group of three in January 2025 uses the October 2024 guideline.
+  period: 2025-01
+  absolute_error_margin: 0.01
+  input:
+    state_code: SC
+    sc_tanf_benefit_group_size: 3
+  output:
+    # (15,060 + 2 x 5,380) / 12 = 2,151.67; x 0.5 = 1,075.83
+    sc_tanf_need_standard: 1_075.83
+
+- name: Case 2, benefit group of three in October 2025 uses the October 2025 guideline.
+  period: 2025-10
+  absolute_error_margin: 0.01
+  input:
+    state_code:
+      2025: SC
+    sc_tanf_benefit_group_size: 3
+  output:
+    # (15,650 + 2 x 5,500) / 12 = 2,220.83; x 0.5 = 1,110.42
+    sc_tanf_need_standard: 1_110.42
+
+- name: Case 3, an empty benefit group has no need standard.
+  period: 2025-01
+  input:
+    state_code: SC
+    sc_tanf_benefit_group_size: 0
+  output:
+    sc_tanf_need_standard: 0
diff --git a/policyengine_us/tests/policy/baseline/gov/states/sc/tanf/sc_tanf_ssi_recipient.yaml b/policyengine_us/tests/policy/baseline/gov/states/sc/tanf/sc_tanf_ssi_recipient.yaml
new file mode 100644
index 00000000000..61ea5e4862f
--- /dev/null
+++ b/policyengine_us/tests/policy/baseline/gov/states/sc/tanf/sc_tanf_ssi_recipient.yaml
@@ -0,0 +1,33 @@
+# SC DSS TANF Policy Manual (Volume 67), Section 7.7, SSI benefit (page 117).
+
+- name: Case 1, reported SSI receipt.
+  period: 2025-01
+  input:
+    state_code: SC
+    receives_ssi: true
+  output:
+    sc_tanf_ssi_recipient: true
+
+- name: Case 2, an SSI payment.
+  period: 2025-01
+  input:
+    state_code: SC
+    ssi: 500
+  output:
+    sc_tanf_ssi_recipient: true
+
+- name: Case 3, no SSI.
+  period: 2025-01
+  input:
+    state_code: SC
+    age: 35
+  output:
+    sc_tanf_ssi_recipient: false
+
+- name: Case 4, not defined outside South Carolina.
+  period: 2025-01
+  input:
+    state_code: NC
+    receives_ssi: true
+  output:
+    sc_tanf_ssi_recipient: false
diff --git a/policyengine_us/tests/test_sc_tanf_unearned_income_invariants.py b/policyengine_us/tests/test_sc_tanf_unearned_income_invariants.py
new file mode 100644
index 00000000000..b1008275d5f
--- /dev/null
+++ b/policyengine_us/tests/test_sc_tanf_unearned_income_invariants.py
@@ -0,0 +1,344 @@
+"""Property tests: South Carolina TANF gross income and need standard.
+
+SC DSS TANF Policy Manual, Volume 67 (effective August 1, 2026):
+
+- Section 7.1 (PDF page 102): "Income is money received by a BG member (s)
+  from any source." A discharged debt is not money received.
+- Section 7.7 (pages 107-120) counts Social Security at the gross amount
+  (page 116), unemployment compensation (page 118), pensions (page 115),
+  child support (page 108) and VA benefits (page 119), and counts interest,
+  dividends and royalties with "Up to $400 per BG annually ... excluded.
+  Income above $400 must be averaged over the period of the remaining 12
+  months" (page 113).
+- Sections 3.6 (page 56) and 7.7 (page 117): "Exclude the SSI recipient,
+  his/her income, resources and SSI payments in determining benefits for
+  other BG members."
+- Section 8.15 (page 133): the need standard is 50% of the federal poverty
+  guideline for the number of persons in the benefit group, revised each
+  October 1. For January 2025 the guideline is the one in Volume 65's
+  table (PDF page 132): $15,060 for one person plus $5,380 for each
+  additional person.
+
+For every benefit group, in January 2025:
+
+1. Each member's sc_tanf_gross_unearned_income equals a reference written
+   from the manual, not from the model's parameter list: the member's
+   counted sources plus their interest and dividends (floored at zero), less
+   a share of min(group interest and dividends, 400 / 12) proportional to
+   the member's interest and dividends. SSI recipients count nothing and
+   take no share.
+2. The group's total is its counted sources less min(group interest and
+   dividends, 400 / 12), and no member's exclusion exceeds the member's own
+   interest and dividends.
+3. Discharged debt and wages never change unearned income, and negative
+   interest never reduces other income (property 1 holds with them present).
+4. sc_tanf_gross_earned_income is wages, or zero for an SSI recipient.
+5. Raising the head's interest by d raises the group's unearned income by
+   between 0 and d / 12, by exactly the rise in the head's floored interest
+   when the group's interest and dividends already exceed the exclusion, and
+   by 0 when the head receives SSI.
+6. The benefit group size is the number of members who do not receive SSI,
+   and the need standard is 50% of the guideline for that size (0 for an
+   empty group).
+7. Net amounts that can be losses (trust and estate, rental and
+   partnership income here) count only when positive, so a loss never
+   offsets another source or another member's income.
+8. Countable resources are the unit's cash assets less SSI recipients' own
+   bank, stock and bond assets (Sections 3.6 and 7.7).
+
+Each generated group is simulated twice in one vectorized simulation: as
+drawn, and with the head's interest raised (property 5).
+"""
+
+import numpy as np
+import pytest
+
+from policyengine_us import Simulation
+
+YEAR = 2025
+MONTH = f"{YEAR}-01"
+EXCLUSION = 400  # Section 7.7, page 113, per benefit group per year.
+# Volume 65, Section 8.15 (PDF page 132): in effect from October 2024.
+FPG_FIRST_PERSON = 15_060
+FPG_ADDITIONAL_PERSON = 5_380
+NEED_STANDARD_RATE = 0.5
+TOLERANCE = 0.01
+
+# Sources counted at the gross amount, in model input names.
+COUNTED = [
+    "social_security_retirement",
+    "unemployment_compensation",
+    "taxable_private_pension_income",
+    "tax_exempt_private_pension_income",
+    "taxable_ira_distributions",
+    "child_support_received",
+    "veterans_benefits",
+]
+INTEREST_AND_DIVIDENDS = [
+    "taxable_interest_income",
+    "tax_exempt_interest_income",
+    "qualified_dividend_income",
+    "non_qualified_dividend_income",
+]
+# Net amounts counted only when positive. partnership_income is the only
+# component drawn of partnership_s_corp_income, so flooring it matches the
+# model's floor on that total.
+POSITIVE_ONLY = ["estate_income", "rental_income", "partnership_income"]
+# Inputs that must not count as unearned income.
+IGNORED = ["debt_relief"]
+ASSETS = ["bank_account_assets", "stock_assets", "bond_assets"]
+WAGES = "employment_income_before_lsr"
+AMOUNT_INPUTS = [
+    *COUNTED,
+    *POSITIVE_ONLY,
+    *INTEREST_AND_DIVIDENDS,
+    *IGNORED,
+    WAGES,
+    *ASSETS,
+]
+
+
+def build_situation(groups):
+    """One household, SPM unit, tax unit and family per group; each person
+    is unmarried. Adults are 30 to 50 and children 1 to 17, and nobody is
+    disabled, so the model computes no SSI; SSI receipt comes only from
+    receives_ssi."""
+    people, tax_units, spm_units, families, households = {}, {}, {}, {}, {}
+    marital_units = {}
+    for i, group in enumerate(groups):
+        members = []
+        for j, member in enumerate(group):
+            name = f"person_{i}_{j}"
+            person = {
+                "age": {YEAR: member["age"]},
+                "receives_ssi": {MONTH: member["ssi"]},
+            }
+            for variable in AMOUNT_INPUTS:
+                person[variable] = {YEAR: member.get(variable, 0)}
+            people[name] = person
+            members.append(name)
+            marital_units[f"marital_unit_{i}_{j}"] = {"members": [name]}
+        tax_units[f"tax_unit_{i}"] = {"members": members}
+        spm_units[f"spm_unit_{i}"] = {"members": members}
+        families[f"family_{i}"] = {"members": members}
+        households[f"household_{i}"] = {
+            "members": members,
+            "state_code": {YEAR: "SC"},
+        }
+    return {
+        "people": people,
+        "tax_units": tax_units,
+        "spm_units": spm_units,
+        "families": families,
+        "marital_units": marital_units,
+        "households": households,
+    }
+
+
+def raise_head_interest(group, d):
+    raised = [dict(member) for member in group]
+    raised[0]["taxable_interest_income"] = (
+        raised[0].get("taxable_interest_income", 0) + d
+    )
+    return raised
+
+
+def member_interest_and_dividends(member):
+    """Monthly interest and dividends counted for a member: floored at zero,
+    and zero for an SSI recipient."""
+    if member["ssi"]:
+        return 0
+    return max(sum(member.get(v, 0) for v in INTEREST_AND_DIVIDENDS), 0) / 12
+
+
+def member_counted(member):
+    """Monthly counted income before the exclusion."""
+    if member["ssi"]:
+        return 0
+    other = sum(member.get(v, 0) for v in COUNTED) / 12
+    other += sum(max(member.get(v, 0), 0) for v in POSITIVE_ONLY) / 12
+    return other + member_interest_and_dividends(member)
+
+
+def reference(group):
+    """Monthly gross unearned and earned income per member, the group's
+    exclusion, and the benefit group's size and need standard, from the
+    manual."""
+    idr = [member_interest_and_dividends(m) for m in group]
+    group_idr = sum(idr)
+    exclusion = min(group_idr, EXCLUSION / 12)
+    unearned = [
+        member_counted(m) - (exclusion * x / group_idr if group_idr > 0 else 0)
+        for m, x in zip(group, idr)
+    ]
+    earned = [0 if m["ssi"] else m.get(WAGES, 0) / 12 for m in group]
+    size = sum(not m["ssi"] for m in group)
+    fpg = (FPG_FIRST_PERSON + FPG_ADDITIONAL_PERSON * (size - 1)) / 12
+    need_standard = NEED_STANDARD_RATE * fpg if size > 0 else 0
+    resources = sum(sum(m.get(v, 0) for v in ASSETS) for m in group if not m["ssi"])
+    return unearned, earned, exclusion, size, need_standard, resources
+
+
+def run(groups, raises):
+    """Simulate each group as drawn and with the head's interest raised.
+    Return per-member and per-group values for both copies."""
+    doubled = groups + [raise_head_interest(g, d) for g, d in zip(groups, raises)]
+    sim = Simulation(situation=build_situation(doubled))
+
+    def calc(variable):
+        return np.asarray(sim.calculate(variable, MONTH))
+
+    unearned = calc("sc_tanf_gross_unearned_income")
+    earned = calc("sc_tanf_gross_earned_income")
+    ssi = calc("sc_tanf_ssi_recipient")
+    size = calc("sc_tanf_benefit_group_size")
+    need = calc("sc_tanf_need_standard")
+    resources = calc("sc_tanf_countable_resources")
+    bounds = np.cumsum([0, *[len(g) for g in doubled]])
+    n = len(groups)
+
+    def split(a):
+        return [a[bounds[k] : bounds[k + 1]] for k in range(len(doubled))]
+
+    u, e, s = split(unearned), split(earned), split(ssi)
+    drawn = (u[:n], e[:n], s[:n], size[:n], need[:n], resources[:n])
+    raised = (u[n:], e[n:], s[n:], size[n:], need[n:], resources[n:])
+    return drawn, raised
+
+
+def check(groups, raises):
+    (unearned, earned, ssi, size, need, resources), raised = run(groups, raises)
+    raised_unearned = raised[0]
+    for k, group in enumerate(groups):
+        expected = reference(group)
+        expected_unearned, expected_earned, exclusion = expected[:3]
+        expected_size, expected_need, expected_resources = expected[3:]
+        context = {"group": group}
+        # Properties 1 and 3: the reference from the manual.
+        assert unearned[k] == pytest.approx(expected_unearned, abs=TOLERANCE), context
+        # Property 4.
+        assert earned[k] == pytest.approx(expected_earned, abs=TOLERANCE), context
+        assert list(ssi[k]) == [bool(m["ssi"]) for m in group], context
+        # Property 2: group conservation and per-member bounds.
+        counted = [member_counted(m) for m in group]
+        assert unearned[k].sum() == pytest.approx(
+            sum(counted) - exclusion, abs=TOLERANCE
+        ), context
+        for member, value, before in zip(group, unearned[k], counted):
+            own = member_interest_and_dividends(member)
+            assert -TOLERANCE <= before - value <= own + TOLERANCE, context
+        # Property 5: monotone in the head's interest.
+        change = raised_unearned[k].sum() - unearned[k].sum()
+        d = raises[k] / 12
+        assert -TOLERANCE <= change <= d + TOLERANCE, context
+        head = group[0]
+        head_rise = member_interest_and_dividends(
+            raise_head_interest([head], raises[k])[0]
+        ) - member_interest_and_dividends(head)
+        group_idr = sum(member_interest_and_dividends(m) for m in group)
+        if head["ssi"]:
+            assert change == pytest.approx(0, abs=TOLERANCE), context
+        elif group_idr >= EXCLUSION / 12:
+            assert change == pytest.approx(head_rise, abs=TOLERANCE), context
+        # Property 6: benefit group size and need standard.
+        assert size[k] == expected_size, context
+        assert need[k] == pytest.approx(expected_need, abs=TOLERANCE), context
+        # Property 8: SSI recipients' own assets are left out.
+        assert resources[k] == pytest.approx(expected_resources, abs=TOLERANCE), context
+
+
+def test_worked_example():
+    """Integration Case 9's benefit group, from the manual: child support
+    3,600, interest 1,000, and a child's Social Security 4,800 a year."""
+    groups = [
+        [
+            {
+                "age": 30,
+                "ssi": False,
+                "child_support_received": 3_600,
+                "taxable_interest_income": 1_000,
+            },
+            {"age": 9, "ssi": False, "social_security_retirement": 4_800},
+            {"age": 6, "ssi": False},
+        ]
+    ]
+    (unearned, _, _, size, need, _), _ = run(groups, [0])
+    # 300 + (1,000 - 400) / 12 = 350 for the parent; 400 for the child.
+    assert unearned[0] == pytest.approx([350, 400, 0], abs=TOLERANCE)
+    # Volume 65 Section 8.15 guideline, three persons: (15,060 + 2 x 5,380) / 12 x 0.5.
+    assert size[0] == 3
+    assert need[0] == pytest.approx(1_075.83, abs=TOLERANCE)
+
+
+try:
+    import hypothesis
+    import hypothesis.strategies as st
+except ImportError:  # pragma: no cover
+    hypothesis = None
+
+if hypothesis is not None:
+    SLOW = [hypothesis.HealthCheck.too_slow]
+
+    def amount(high):
+        return st.one_of(st.just(0), st.integers(min_value=1, max_value=high))
+
+    def signed(high):
+        return st.one_of(amount(high), st.integers(min_value=-high, max_value=-1))
+
+    @st.composite
+    def member(draw, age):
+        return {
+            "age": age,
+            "ssi": draw(st.booleans()),
+            "social_security_retirement": draw(amount(24_000)),
+            "unemployment_compensation": draw(amount(15_000)),
+            "taxable_private_pension_income": draw(amount(10_000)),
+            "tax_exempt_private_pension_income": draw(amount(5_000)),
+            "taxable_ira_distributions": draw(amount(20_000)),
+            "child_support_received": draw(amount(8_000)),
+            "veterans_benefits": draw(amount(12_000)),
+            # Negative interest is allowed as an input and must not offset
+            # other income.
+            "taxable_interest_income": draw(
+                st.one_of(amount(3_000), st.integers(min_value=-3_000, max_value=-1))
+            ),
+            "tax_exempt_interest_income": draw(amount(1_000)),
+            "qualified_dividend_income": draw(amount(2_000)),
+            "non_qualified_dividend_income": draw(amount(1_000)),
+            # Signed net amounts, like Schedule E income or loss.
+            "estate_income": draw(signed(6_000)),
+            "rental_income": draw(signed(8_000)),
+            "partnership_income": draw(signed(8_000)),
+            "debt_relief": draw(amount(5_000)),
+            "bank_account_assets": draw(amount(3_000)),
+            "stock_assets": draw(amount(2_000)),
+            "bond_assets": draw(amount(1_000)),
+            "employment_income_before_lsr": draw(amount(30_000)),
+        }
+
+    @st.composite
+    def group(draw):
+        head = draw(member(draw(st.integers(min_value=30, max_value=50))))
+        children = draw(
+            st.lists(
+                member(draw(st.integers(min_value=1, max_value=17))),
+                min_size=0,
+                max_size=3,
+            )
+        )
+        return [head, *children]
+
+    @hypothesis.settings(
+        max_examples=15, derandomize=True, deadline=None, suppress_health_check=SLOW
+    )
+    @hypothesis.given(
+        st.lists(
+            st.tuples(group(), st.integers(min_value=1, max_value=5_000)),
+            min_size=1,
+            max_size=8,
+        )
+    )
+    def test_properties(cases):
+        groups = [g for g, _ in cases]
+        raises = [d for _, d in cases]
+        check(groups, raises)
diff --git a/policyengine_us/variables/gov/states/sc/tanf/eligibility/sc_tanf_countable_income_eligible.py b/policyengine_us/variables/gov/states/sc/tanf/eligibility/sc_tanf_countable_income_eligible.py
index d91f33f82ef..f6583d47d06 100644
--- a/policyengine_us/variables/gov/states/sc/tanf/eligibility/sc_tanf_countable_income_eligible.py
+++ b/policyengine_us/variables/gov/states/sc/tanf/eligibility/sc_tanf_countable_income_eligible.py
@@ -12,8 +12,6 @@ class sc_tanf_countable_income_eligible(Variable):
     )
 
     def formula(spm_unit, period, parameters):
-        p = parameters(period).gov.states.sc.tanf.income
-        fpg = spm_unit("tanf_fpg", period)
-        need_standard = fpg * p.need_standard.rate
+        need_standard = spm_unit("sc_tanf_need_standard", period)
         countable_income = spm_unit("sc_tanf_countable_income", period)
         return countable_income < need_standard
diff --git a/policyengine_us/variables/gov/states/sc/tanf/eligibility/sc_tanf_countable_resources.py b/policyengine_us/variables/gov/states/sc/tanf/eligibility/sc_tanf_countable_resources.py
new file mode 100644
index 00000000000..dabae216069
--- /dev/null
+++ b/policyengine_us/variables/gov/states/sc/tanf/eligibility/sc_tanf_countable_resources.py
@@ -0,0 +1,32 @@
+from policyengine_us.model_api import *
+
+
+class sc_tanf_countable_resources(Variable):
+    value_type = float
+    entity = SPMUnit
+    label = "South Carolina TANF countable resources"
+    unit = USD
+    definition_period = MONTH
+    quantity_type = STOCK
+    defined_for = StateCode.SC
+    # PDF pages 56, 91, 117
+    reference = "https://dss.sc.gov/media/bxwc1jdj/tanf-policy-manual-volume-67-final.pdf#page=56"  # Sections 3.6, 6.4 and 7.7
+
+    def formula(spm_unit, period, parameters):
+        # Sections 3.6 and 7.7 exclude the SSI recipient's resources along
+        # with his or her income and needs. The excluded people's assets are
+        # subtracted from the unit aggregate rather than the total being
+        # rebuilt from person-level values, so households that supply only
+        # the spm_unit_cash_assets aggregate keep the aggregate behavior.
+        total = spm_unit("spm_unit_cash_assets", period.this_year)
+        person = spm_unit.members
+        ssi_recipient = person("sc_tanf_ssi_recipient", period)
+        # This component list must mirror spm_unit_cash_assets.adds, so the
+        # subtraction removes exactly the excluded members' share.
+        person_assets = add(
+            person,
+            period.this_year,
+            ["bank_account_assets", "stock_assets", "bond_assets"],
+        )
+        excluded_assets = spm_unit.sum(person_assets * ssi_recipient)
+        return max_(total - excluded_assets, 0)
diff --git a/policyengine_us/variables/gov/states/sc/tanf/eligibility/sc_tanf_gross_income_eligible.py b/policyengine_us/variables/gov/states/sc/tanf/eligibility/sc_tanf_gross_income_eligible.py
index 63da1a846f1..61ac97c146d 100644
--- a/policyengine_us/variables/gov/states/sc/tanf/eligibility/sc_tanf_gross_income_eligible.py
+++ b/policyengine_us/variables/gov/states/sc/tanf/eligibility/sc_tanf_gross_income_eligible.py
@@ -13,8 +13,7 @@ class sc_tanf_gross_income_eligible(Variable):
 
     def formula(spm_unit, period, parameters):
         p = parameters(period).gov.states.sc.tanf.income
-        fpg = spm_unit("tanf_fpg", period)
-        need_standard = fpg * p.need_standard.rate
+        need_standard = spm_unit("sc_tanf_need_standard", period)
         gross_income_limit = need_standard * p.gross_income_limit
         gross_income = spm_unit("sc_tanf_gross_income", period)
         return gross_income <= gross_income_limit
diff --git a/policyengine_us/variables/gov/states/sc/tanf/eligibility/sc_tanf_resources_eligible.py b/policyengine_us/variables/gov/states/sc/tanf/eligibility/sc_tanf_resources_eligible.py
index 181d4a32c21..1e6c3f92bac 100644
--- a/policyengine_us/variables/gov/states/sc/tanf/eligibility/sc_tanf_resources_eligible.py
+++ b/policyengine_us/variables/gov/states/sc/tanf/eligibility/sc_tanf_resources_eligible.py
@@ -11,5 +11,5 @@ class sc_tanf_resources_eligible(Variable):
 
     def formula(spm_unit, period, parameters):
         p = parameters(period).gov.states.sc.tanf.resources
-        assets = spm_unit("spm_unit_cash_assets", period.this_year)
+        assets = spm_unit("sc_tanf_countable_resources", period)
         return assets <= p.limit
diff --git a/policyengine_us/variables/gov/states/sc/tanf/income/sc_tanf_gross_earned_income.py b/policyengine_us/variables/gov/states/sc/tanf/income/sc_tanf_gross_earned_income.py
index 7c599d576d3..f63cbfc90fd 100644
--- a/policyengine_us/variables/gov/states/sc/tanf/income/sc_tanf_gross_earned_income.py
+++ b/policyengine_us/variables/gov/states/sc/tanf/income/sc_tanf_gross_earned_income.py
@@ -8,5 +8,11 @@ class sc_tanf_gross_earned_income(Variable):
     unit = USD
     definition_period = MONTH
     defined_for = StateCode.SC
-    reference = "https://dss.sc.gov/media/ojqddxsk/tanf-policy-manual-volume-65.pdf#page=100"  # Section 7.1
-    adds = "gov.states.sc.tanf.income.earned.earned"
+    # PDF pages 102, 112, 117
+    reference = "https://dss.sc.gov/media/bxwc1jdj/tanf-policy-manual-volume-67-final.pdf#page=102"  # Sections 7.1 and 7.7
+
+    def formula(person, period, parameters):
+        p = parameters(period).gov.states.sc.tanf.income.earned
+        earned = add(person, period, p.earned)
+        # Section 7.7 excludes the income of SSI recipients.
+        return earned * ~person("sc_tanf_ssi_recipient", period)
diff --git a/policyengine_us/variables/gov/states/sc/tanf/income/sc_tanf_gross_unearned_income.py b/policyengine_us/variables/gov/states/sc/tanf/income/sc_tanf_gross_unearned_income.py
index 36273d0a264..2368dd07f73 100644
--- a/policyengine_us/variables/gov/states/sc/tanf/income/sc_tanf_gross_unearned_income.py
+++ b/policyengine_us/variables/gov/states/sc/tanf/income/sc_tanf_gross_unearned_income.py
@@ -8,5 +8,32 @@ class sc_tanf_gross_unearned_income(Variable):
     unit = USD
     definition_period = MONTH
     defined_for = StateCode.SC
-    reference = "https://dss.sc.gov/media/ojqddxsk/tanf-policy-manual-volume-65.pdf#page=100"  # Section 7.1
-    adds = "gov.states.sc.tanf.income.unearned"
+    # PDF pages 102, 107-120
+    reference = "https://dss.sc.gov/media/bxwc1jdj/tanf-policy-manual-volume-67-final.pdf#page=102"  # Sections 7.1 and 7.7
+
+    def formula(person, period, parameters):
+        p = parameters(period).gov.states.sc.tanf.income.unearned
+        # Section 7.7 excludes the income of SSI recipients.
+        counted = ~person("sc_tanf_ssi_recipient", period)
+        other_sources = add(person, period, p.sources)
+        # Net amounts that can be losses count only when positive: a loss is
+        # not money received (Section 7.1).
+        for source in p.positive_sources:
+            other_sources = other_sources + max_(add(person, period, [source]), 0)
+        other_sources = other_sources * counted
+        # Section 7.7 excludes up to $400 of interest, dividends and royalties
+        # per benefit group each year and averages the rest over 12 months.
+        # Each member's exclusion is proportional to their share of that income.
+        p_idr = p.interest_and_dividends
+        interest_and_dividends = max_(add(person, period, p_idr.sources), 0) * counted
+        unit_interest_and_dividends = person.spm_unit.sum(interest_and_dividends)
+        unit_exclusion = min_(
+            unit_interest_and_dividends, p_idr.exclusion / MONTHS_IN_YEAR
+        )
+        share = np.divide(
+            interest_and_dividends,
+            unit_interest_and_dividends,
+            out=np.zeros_like(interest_and_dividends),
+            where=unit_interest_and_dividends > 0,
+        )
+        return other_sources + interest_and_dividends - unit_exclusion * share
diff --git a/policyengine_us/variables/gov/states/sc/tanf/sc_tanf.py b/policyengine_us/variables/gov/states/sc/tanf/sc_tanf.py
index 061c427ad58..c5e491e4d7a 100644
--- a/policyengine_us/variables/gov/states/sc/tanf/sc_tanf.py
+++ b/policyengine_us/variables/gov/states/sc/tanf/sc_tanf.py
@@ -14,9 +14,7 @@ class sc_tanf(Variable):
 
     def formula(spm_unit, period, parameters):
         p = parameters(period).gov.states.sc.tanf
-        # Compute need standard based on federal poverty guidelines
-        fpg = spm_unit("tanf_fpg", period)
-        need_standard = fpg * p.income.need_standard.rate
+        need_standard = spm_unit("sc_tanf_need_standard", period)
         countable_income = spm_unit("sc_tanf_countable_income", period)
         excess_income = max_(need_standard - countable_income, 0)
         benefit = excess_income * p.payment.rate
diff --git a/policyengine_us/variables/gov/states/sc/tanf/sc_tanf_benefit_group_size.py b/policyengine_us/variables/gov/states/sc/tanf/sc_tanf_benefit_group_size.py
new file mode 100644
index 00000000000..0a73415430c
--- /dev/null
+++ b/policyengine_us/variables/gov/states/sc/tanf/sc_tanf_benefit_group_size.py
@@ -0,0 +1,17 @@
+from policyengine_us.model_api import *
+
+
+class sc_tanf_benefit_group_size(Variable):
+    value_type = int
+    entity = SPMUnit
+    label = "South Carolina TANF benefit group size"
+    definition_period = MONTH
+    defined_for = StateCode.SC
+    # PDF pages 56, 117
+    reference = "https://dss.sc.gov/media/bxwc1jdj/tanf-policy-manual-volume-67-final.pdf#page=56"  # Sections 3.6 and 7.7
+
+    def formula(spm_unit, period, parameters):
+        # Section 3.6 excludes an SSI recipient living with the benefit group;
+        # if an SSI child is the only child, the parents are the only members.
+        ssi_recipient = spm_unit.members("sc_tanf_ssi_recipient", period)
+        return spm_unit.sum(~ssi_recipient)
diff --git a/policyengine_us/variables/gov/states/sc/tanf/sc_tanf_need_standard.py b/policyengine_us/variables/gov/states/sc/tanf/sc_tanf_need_standard.py
new file mode 100644
index 00000000000..1a869558d4b
--- /dev/null
+++ b/policyengine_us/variables/gov/states/sc/tanf/sc_tanf_need_standard.py
@@ -0,0 +1,31 @@
+from policyengine_us.model_api import *
+
+
+class sc_tanf_need_standard(Variable):
+    value_type = float
+    entity = SPMUnit
+    label = "South Carolina TANF need standard"
+    unit = USD
+    definition_period = MONTH
+    defined_for = StateCode.SC
+    # PDF pages 133-134
+    reference = "https://dss.sc.gov/media/bxwc1jdj/tanf-policy-manual-volume-67-final.pdf#page=133"  # Sections 8.15 and 8.16
+
+    def formula(spm_unit, period, parameters):
+        p = parameters(period).gov.states.sc.tanf.income.need_standard
+        size = spm_unit("sc_tanf_benefit_group_size", period)
+        # Section 8.15 sets the need standard as a share of the federal
+        # poverty guideline for the number of persons in the benefit group,
+        # revised each October 1, as in tanf_fpg.
+        year = period.start.year
+        if period.start.month >= 10:
+            instant_str = f"{year}-10-01"
+        else:
+            instant_str = f"{year - 1}-10-01"
+        p_fpg = parameters(instant_str).gov.hhs.fpg
+        state_group = spm_unit.household("state_group_str", period.this_year)
+        fpg = (
+            p_fpg.first_person[state_group]
+            + p_fpg.additional_person[state_group] * (size - 1)
+        ) / MONTHS_IN_YEAR
+        return where(size > 0, fpg * p.rate, 0)
diff --git a/policyengine_us/variables/gov/states/sc/tanf/sc_tanf_ssi_recipient.py b/policyengine_us/variables/gov/states/sc/tanf/sc_tanf_ssi_recipient.py
new file mode 100644
index 00000000000..276a3442394
--- /dev/null
+++ b/policyengine_us/variables/gov/states/sc/tanf/sc_tanf_ssi_recipient.py
@@ -0,0 +1,16 @@
+from policyengine_us.model_api import *
+
+
+class sc_tanf_ssi_recipient(Variable):
+    value_type = bool
+    entity = Person
+    label = "South Carolina TANF SSI recipient"
+    definition_period = MONTH
+    defined_for = StateCode.SC
+    reference = "https://dss.sc.gov/media/bxwc1jdj/tanf-policy-manual-volume-67-final.pdf#page=117"  # Section 7.7, SSI benefit
+
+    def formula(person, period, parameters):
+        # Section 7.7 excludes the SSI recipient and his or her income when
+        # determining benefits for the other benefit group members. Reported
+        # receipt also counts, covering people the model computes as $0.
+        return (person("ssi", period) > 0) | person("receives_ssi", period)