diff --git a/changelog_entry.yaml b/changelog_entry.yaml
index e69de29bb2d..f84570f7f15 100644
--- a/changelog_entry.yaml
+++ b/changelog_entry.yaml
@@ -0,0 +1,4 @@
+- bump: minor
+  changes:
+    added:
+      - Add Washington Apple Health for Kids and Apple Health Expansion programs.
diff --git a/policyengine_us/parameters/gov/states/wa/hca/apple_health/expansion/eligibility/in_effect.yaml b/policyengine_us/parameters/gov/states/wa/hca/apple_health/expansion/eligibility/in_effect.yaml
new file mode 100644
index 00000000000..265bf773b48
--- /dev/null
+++ b/policyengine_us/parameters/gov/states/wa/hca/apple_health/expansion/eligibility/in_effect.yaml
@@ -0,0 +1,16 @@
+description: Washington provides Apple Health Expansion coverage for eligible adults.
+metadata:
+  unit: bool
+  period: year
+  label: Washington Apple Health Expansion program in effect
+  reference:
+    - title: WAC 182-525-0300 - Apple Health expansion coverage
+      href: https://app.leg.wa.gov/wac/default.aspx?cite=182-525-0300
+    - title: HCA Apple Health Expansion Overview
+      href: https://www.hca.wa.gov/about-hca/programs-and-initiatives/apple-health-medicaid/apple-health-expansion
+    - title: ESSB 5187 Section 211(83) - 2023-2025 budget proviso
+      href: https://lawfilesext.leg.wa.gov/biennium/2023-24/Pdf/Bills/Session%20Laws/Senate/5187-S.SL.pdf
+
+values:
+  2020-01-01: false
+  2024-06-21: true
diff --git a/policyengine_us/parameters/gov/states/wa/hca/apple_health/expansion/eligibility/income_limit.yaml b/policyengine_us/parameters/gov/states/wa/hca/apple_health/expansion/eligibility/income_limit.yaml
new file mode 100644
index 00000000000..113182a26a1
--- /dev/null
+++ b/policyengine_us/parameters/gov/states/wa/hca/apple_health/expansion/eligibility/income_limit.yaml
@@ -0,0 +1,13 @@
+description: Washington sets this income limit for Apple Health Expansion as a fraction of FPL.
+metadata:
+  unit: /1
+  period: year
+  label: Washington Apple Health Expansion income limit as fraction of FPL
+  reference:
+    - title: WAC 182-525-0300 - Apple Health expansion coverage
+      href: https://app.leg.wa.gov/wac/default.aspx?cite=182-525-0300
+    - title: HCA Income Standards (HCA 19-0096)
+      href: https://www.hca.wa.gov/assets/free-or-low-cost/income-standards.pdf
+
+values:
+  2024-06-21: 1.38
diff --git a/policyengine_us/parameters/gov/states/wa/hca/apple_health/expansion/eligibility/min_age.yaml b/policyengine_us/parameters/gov/states/wa/hca/apple_health/expansion/eligibility/min_age.yaml
new file mode 100644
index 00000000000..fe2a49ae776
--- /dev/null
+++ b/policyengine_us/parameters/gov/states/wa/hca/apple_health/expansion/eligibility/min_age.yaml
@@ -0,0 +1,11 @@
+description: Washington requires this minimum age for Apple Health Expansion.
+metadata:
+  unit: year
+  period: year
+  label: Washington Apple Health Expansion minimum age
+  reference:
+    - title: WAC 182-525-0300 - Apple Health expansion coverage
+      href: https://app.leg.wa.gov/wac/default.aspx?cite=182-525-0300
+
+values:
+  2024-06-21: 19
diff --git a/policyengine_us/parameters/gov/states/wa/hca/apple_health/kids/eligibility/age_limit.yaml b/policyengine_us/parameters/gov/states/wa/hca/apple_health/kids/eligibility/age_limit.yaml
new file mode 100644
index 00000000000..ee299413c72
--- /dev/null
+++ b/policyengine_us/parameters/gov/states/wa/hca/apple_health/kids/eligibility/age_limit.yaml
@@ -0,0 +1,13 @@
+description: Washington sets this maximum age for Apple Health for Kids.
+metadata:
+  unit: year
+  period: year
+  label: Washington Apple Health for Kids maximum age
+  reference:
+    - title: RCW 74.09.470 - Medical care for children
+      href: https://app.leg.wa.gov/rcw/default.aspx?cite=74.09.470
+    - title: WAC 182-505-0210 - Children's eligibility
+      href: https://app.leg.wa.gov/wac/default.aspx?cite=182-505-0210
+
+values:
+  2019-01-01: 19
diff --git a/policyengine_us/parameters/gov/states/wa/hca/apple_health/kids/eligibility/in_effect.yaml b/policyengine_us/parameters/gov/states/wa/hca/apple_health/kids/eligibility/in_effect.yaml
new file mode 100644
index 00000000000..aaccbada430
--- /dev/null
+++ b/policyengine_us/parameters/gov/states/wa/hca/apple_health/kids/eligibility/in_effect.yaml
@@ -0,0 +1,13 @@
+description: Washington provides Apple Health for Kids coverage for eligible children.
+metadata:
+  unit: bool
+  period: year
+  label: Washington Apple Health for Kids program in effect
+  reference:
+    - title: RCW 74.09.470 - Medical care for children
+      href: https://app.leg.wa.gov/rcw/default.aspx?cite=74.09.470
+    - title: HCA Apple Health for Children
+      href: https://www.hca.wa.gov/free-or-low-cost-health-care/i-need-medical-dental-or-vision-care/children
+
+values:
+  2019-01-01: true
diff --git a/policyengine_us/parameters/gov/states/wa/hca/apple_health/kids/income_limit/free.yaml b/policyengine_us/parameters/gov/states/wa/hca/apple_health/kids/income_limit/free.yaml
new file mode 100644
index 00000000000..3b875ea8041
--- /dev/null
+++ b/policyengine_us/parameters/gov/states/wa/hca/apple_health/kids/income_limit/free.yaml
@@ -0,0 +1,13 @@
+description: Washington sets this income limit for free Apple Health for Kids coverage as a fraction of FPL.
+metadata:
+  unit: /1
+  period: year
+  label: Washington Apple Health for Kids free coverage income limit as fraction of FPL
+  reference:
+    - title: WAC 182-505-0100 - Income standards (210% FPL statutory)
+      href: https://app.leg.wa.gov/wac/default.aspx?cite=182-505-0100
+    - title: HCA Income Standards (HCA 19-0096) - operational thresholds with 5pp disregard
+      href: https://www.hca.wa.gov/assets/free-or-low-cost/income-standards.pdf
+
+values:
+  2019-01-01: 2.15
diff --git a/policyengine_us/parameters/gov/states/wa/hca/apple_health/kids/income_limit/tier_1.yaml b/policyengine_us/parameters/gov/states/wa/hca/apple_health/kids/income_limit/tier_1.yaml
new file mode 100644
index 00000000000..6dabb321408
--- /dev/null
+++ b/policyengine_us/parameters/gov/states/wa/hca/apple_health/kids/income_limit/tier_1.yaml
@@ -0,0 +1,13 @@
+description: Washington sets this income limit for Apple Health for Kids Tier 1 as a fraction of FPL.
+metadata:
+  unit: /1
+  period: year
+  label: Washington Apple Health for Kids Tier 1 income limit as fraction of FPL
+  reference:
+    - title: WAC 182-505-0225 - Premium requirements (260% FPL statutory)
+      href: https://app.leg.wa.gov/wac/default.aspx?cite=182-505-0225
+    - title: HCA Income Standards (HCA 19-0096) - operational thresholds with 5pp disregard
+      href: https://www.hca.wa.gov/assets/free-or-low-cost/income-standards.pdf
+
+values:
+  2019-01-01: 2.65
diff --git a/policyengine_us/parameters/gov/states/wa/hca/apple_health/kids/income_limit/tier_2.yaml b/policyengine_us/parameters/gov/states/wa/hca/apple_health/kids/income_limit/tier_2.yaml
new file mode 100644
index 00000000000..05e83a1f62c
--- /dev/null
+++ b/policyengine_us/parameters/gov/states/wa/hca/apple_health/kids/income_limit/tier_2.yaml
@@ -0,0 +1,13 @@
+description: Washington sets this income limit for Apple Health for Kids Tier 2 as a fraction of FPL.
+metadata:
+  unit: /1
+  period: year
+  label: Washington Apple Health for Kids Tier 2 income limit as fraction of FPL
+  reference:
+    - title: WAC 182-505-0100 - Income standards (312% FPL statutory)
+      href: https://app.leg.wa.gov/wac/default.aspx?cite=182-505-0100
+    - title: HCA Income Standards (HCA 19-0096) - operational thresholds with 5pp disregard
+      href: https://www.hca.wa.gov/assets/free-or-low-cost/income-standards.pdf
+
+values:
+  2019-01-01: 3.17
diff --git a/policyengine_us/parameters/gov/states/wa/hca/apple_health/kids/premium/tier_1_household_max.yaml b/policyengine_us/parameters/gov/states/wa/hca/apple_health/kids/premium/tier_1_household_max.yaml
new file mode 100644
index 00000000000..a9d683ad625
--- /dev/null
+++ b/policyengine_us/parameters/gov/states/wa/hca/apple_health/kids/premium/tier_1_household_max.yaml
@@ -0,0 +1,13 @@
+description: Washington sets this maximum household premium for Apple Health for Kids Tier 1.
+metadata:
+  unit: currency-USD
+  period: month
+  label: Washington Apple Health for Kids Tier 1 household maximum premium
+  reference:
+    - title: WAC 182-505-0225 - Premium requirements (no more than 2 children)
+      href: https://app.leg.wa.gov/wac/default.aspx?cite=182-505-0225
+    - title: HCA Income Standards (HCA 19-0096)
+      href: https://www.hca.wa.gov/assets/free-or-low-cost/income-standards.pdf
+
+values:
+  2019-01-01: 40
diff --git a/policyengine_us/parameters/gov/states/wa/hca/apple_health/kids/premium/tier_1_per_child.yaml b/policyengine_us/parameters/gov/states/wa/hca/apple_health/kids/premium/tier_1_per_child.yaml
new file mode 100644
index 00000000000..e4522370f12
--- /dev/null
+++ b/policyengine_us/parameters/gov/states/wa/hca/apple_health/kids/premium/tier_1_per_child.yaml
@@ -0,0 +1,13 @@
+description: Washington sets this per-child premium for Apple Health for Kids Tier 1.
+metadata:
+  unit: currency-USD
+  period: month
+  label: Washington Apple Health for Kids Tier 1 premium per child
+  reference:
+    - title: WAC 182-505-0225 - Premium requirements ($20/child for 210-260% FPL)
+      href: https://app.leg.wa.gov/wac/default.aspx?cite=182-505-0225
+    - title: HCA Income Standards (HCA 19-0096)
+      href: https://www.hca.wa.gov/assets/free-or-low-cost/income-standards.pdf
+
+values:
+  2019-01-01: 20
diff --git a/policyengine_us/parameters/gov/states/wa/hca/apple_health/kids/premium/tier_2_household_max.yaml b/policyengine_us/parameters/gov/states/wa/hca/apple_health/kids/premium/tier_2_household_max.yaml
new file mode 100644
index 00000000000..5176c3ed50f
--- /dev/null
+++ b/policyengine_us/parameters/gov/states/wa/hca/apple_health/kids/premium/tier_2_household_max.yaml
@@ -0,0 +1,13 @@
+description: Washington sets this maximum household premium for Apple Health for Kids Tier 2.
+metadata:
+  unit: currency-USD
+  period: month
+  label: Washington Apple Health for Kids Tier 2 household maximum premium
+  reference:
+    - title: WAC 182-505-0225 - Premium requirements (no more than 2 children)
+      href: https://app.leg.wa.gov/wac/default.aspx?cite=182-505-0225
+    - title: HCA Income Standards (HCA 19-0096)
+      href: https://www.hca.wa.gov/assets/free-or-low-cost/income-standards.pdf
+
+values:
+  2019-01-01: 60
diff --git a/policyengine_us/parameters/gov/states/wa/hca/apple_health/kids/premium/tier_2_per_child.yaml b/policyengine_us/parameters/gov/states/wa/hca/apple_health/kids/premium/tier_2_per_child.yaml
new file mode 100644
index 00000000000..b02f8d9bec6
--- /dev/null
+++ b/policyengine_us/parameters/gov/states/wa/hca/apple_health/kids/premium/tier_2_per_child.yaml
@@ -0,0 +1,13 @@
+description: Washington sets this per-child premium for Apple Health for Kids Tier 2.
+metadata:
+  unit: currency-USD
+  period: month
+  label: Washington Apple Health for Kids Tier 2 premium per child
+  reference:
+    - title: WAC 182-505-0225 - Premium requirements ($30/child for 260-312% FPL)
+      href: https://app.leg.wa.gov/wac/default.aspx?cite=182-505-0225
+    - title: HCA Income Standards (HCA 19-0096)
+      href: https://www.hca.wa.gov/assets/free-or-low-cost/income-standards.pdf
+
+values:
+  2019-01-01: 30
diff --git a/policyengine_us/tests/policy/baseline/gov/states/wa/hca/apple_health/costs/wa_apple_health_cost_if_enrolled.yaml b/policyengine_us/tests/policy/baseline/gov/states/wa/hca/apple_health/costs/wa_apple_health_cost_if_enrolled.yaml
new file mode 100644
index 00000000000..de259894bac
--- /dev/null
+++ b/policyengine_us/tests/policy/baseline/gov/states/wa/hca/apple_health/costs/wa_apple_health_cost_if_enrolled.yaml
@@ -0,0 +1,62 @@
+- name: Eligible child - Apple Health for Kids
+  period: 2024
+  absolute_error_margin: 1
+  input:
+    households:
+      household:
+        state_code: WA
+        members: [child]
+    people:
+      child:
+        age: 10
+        medicaid_income_level: 2.0  # 200% FPL - below 317% threshold
+  output:
+    wa_apple_health_cost_if_enrolled: 3_643.43  # 3,188,000,000 / 875,000
+
+- name: Eligible expansion adult - undocumented
+  period: 2025
+  absolute_error_margin: 1
+  input:
+    households:
+      household:
+        state_code: WA
+        members: [adult]
+    people:
+      adult:
+        age: 35
+        immigration_status: UNDOCUMENTED
+        medicaid_income_level: 1.2  # 120% FPL - below 138% threshold
+        is_pregnant: false
+  output:
+    wa_apple_health_cost_if_enrolled: 8_792.99  # 7,773,000,000 / 884,000
+
+- name: Ineligible - adult citizen (not expansion eligible)
+  period: 2024
+  absolute_error_margin: 0.01
+  input:
+    households:
+      household:
+        state_code: WA
+        members: [adult]
+    people:
+      adult:
+        age: 35
+        immigration_status: CITIZEN
+        medicaid_income_level: 1.2
+  output:
+    wa_apple_health_cost_if_enrolled: 0
+
+- name: Ineligible - child over income threshold
+  period: 2024
+  absolute_error_margin: 0.01
+  input:
+    households:
+      household:
+        state_code: WA
+        members: [child]
+    people:
+      child:
+        age: 10
+        medicaid_income_level: 4.0  # 400% FPL - above 317% threshold
+  output:
+    wa_apple_health_cost_if_enrolled: 0
diff --git a/policyengine_us/tests/policy/baseline/gov/states/wa/hca/apple_health/costs/wa_apple_health_group.yaml b/policyengine_us/tests/policy/baseline/gov/states/wa/hca/apple_health/costs/wa_apple_health_group.yaml
new file mode 100644
index 00000000000..a1ed5adce71
--- /dev/null
+++ b/policyengine_us/tests/policy/baseline/gov/states/wa/hca/apple_health/costs/wa_apple_health_group.yaml
@@ -0,0 +1,31 @@
+# Tests for Washington Apple Health spending group
+
+- name: Apple Health Kids eligible maps to CHILD group
+  period: 2024
+  input:
+    age: 10
+    medicaid_income_level: 2.0  # 200% FPL
+    state_code: WA
+  output:
+    wa_apple_health_group: CHILD
+
+- name: Apple Health Expansion eligible maps to EXPANSION_ADULT group
+  period: 2025
+  input:
+    age: 30
+    immigration_status: UNDOCUMENTED
+    is_pregnant: false
+    medicaid_income_level: 1.0  # 100% FPL
+    state_code: WA
+  output:
+    wa_apple_health_group: EXPANSION_ADULT
+
+- name: Ineligible person maps to NONE group
+  period: 2024
+  input:
+    age: 30
+    immigration_status: CITIZEN
+    medicaid_income_level: 1.0  # 100% FPL
+    state_code: WA
+  output:
+    wa_apple_health_group: NONE
diff --git a/policyengine_us/tests/policy/baseline/gov/states/wa/hca/apple_health/expansion/eligibility/wa_apple_health_expansion_eligible.yaml b/policyengine_us/tests/policy/baseline/gov/states/wa/hca/apple_health/expansion/eligibility/wa_apple_health_expansion_eligible.yaml
new file mode 100644
index 00000000000..16def1c0473
--- /dev/null
+++ b/policyengine_us/tests/policy/baseline/gov/states/wa/hca/apple_health/expansion/eligibility/wa_apple_health_expansion_eligible.yaml
@@ -0,0 +1,122 @@
+# Tests for Washington Apple Health Expansion eligibility
+
+- name: Undocumented adult with low income eligible in 2025
+  period: 2025
+  input:
+    age: 30
+    immigration_status: UNDOCUMENTED
+    is_pregnant: false
+    medicaid_income_level: 1.0  # 100% FPL
+    state_code: WA
+  output:
+    wa_apple_health_expansion_eligible: true
+
+- name: Undocumented adult at income limit eligible
+  period: 2025
+  input:
+    age: 45
+    immigration_status: UNDOCUMENTED
+    is_pregnant: false
+    medicaid_income_level: 1.38  # 138% FPL (at limit)
+    state_code: WA
+  output:
+    wa_apple_health_expansion_eligible: true
+
+- name: Undocumented adult with income above limit NOT eligible
+  period: 2025
+  input:
+    age: 35
+    immigration_status: UNDOCUMENTED
+    is_pregnant: false
+    medicaid_income_level: 1.5  # 150% FPL (above 138% limit)
+    state_code: WA
+  output:
+    wa_apple_health_expansion_eligible: false
+
+- name: US citizen NOT eligible regardless of income
+  period: 2025
+  input:
+    age: 30
+    immigration_status: CITIZEN
+    is_pregnant: false
+    medicaid_income_level: 1.0  # 100% FPL
+    state_code: WA
+  output:
+    wa_apple_health_expansion_eligible: false
+
+- name: Legal permanent resident NOT eligible
+  period: 2025
+  input:
+    age: 30
+    immigration_status: LEGAL_PERMANENT_RESIDENT
+    is_pregnant: false
+    medicaid_income_level: 1.0  # 100% FPL
+    state_code: WA
+  output:
+    wa_apple_health_expansion_eligible: false
+
+- name: DACA recipient NOT eligible (pending HCA clarification)
+  period: 2025
+  input:
+    age: 25
+    immigration_status: DACA
+    is_pregnant: false
+    medicaid_income_level: 1.0  # 100% FPL
+    state_code: WA
+  output:
+    wa_apple_health_expansion_eligible: false
+
+- name: Pregnant undocumented adult NOT eligible (must use pregnancy programs)
+  period: 2025
+  input:
+    age: 28
+    immigration_status: UNDOCUMENTED
+    is_pregnant: true
+    medicaid_income_level: 1.0  # 100% FPL
+    state_code: WA
+  output:
+    wa_apple_health_expansion_eligible: false
+
+- name: Undocumented child NOT eligible (must use Apple Health for Kids)
+  period: 2025
+  input:
+    age: 15
+    immigration_status: UNDOCUMENTED
+    is_pregnant: false
+    medicaid_income_level: 1.0  # 100% FPL
+    state_code: WA
+  output:
+    wa_apple_health_expansion_eligible: false
+
+- name: Program NOT in effect before June 2024
+  period: 2023
+  input:
+    age: 30
+    immigration_status: UNDOCUMENTED
+    is_pregnant: false
+    medicaid_income_level: 1.0  # 100% FPL
+    state_code: WA
+  output:
+    wa_apple_health_expansion_eligible: false
+
+- name: 19-year-old eligible (at minimum age)
+  period: 2025
+  input:
+    age: 19
+    immigration_status: UNDOCUMENTED
+    is_pregnant: false
+    medicaid_income_level: 1.0  # 100% FPL
+    state_code: WA
+  output:
+    wa_apple_health_expansion_eligible: true
+
+- name: 18-year-old NOT eligible (below minimum age)
+  period: 2025
+  input:
+    age: 18
+    immigration_status: UNDOCUMENTED
+    is_pregnant: false
+    medicaid_income_level: 1.0  # 100% FPL
+    state_code: WA
+  output:
+    wa_apple_health_expansion_eligible: false
diff --git a/policyengine_us/tests/policy/baseline/gov/states/wa/hca/apple_health/expansion/eligibility/wa_apple_health_expansion_immigration_status_eligible.yaml b/policyengine_us/tests/policy/baseline/gov/states/wa/hca/apple_health/expansion/eligibility/wa_apple_health_expansion_immigration_status_eligible.yaml
new file mode 100644
index 00000000000..84c1d591f7c
--- /dev/null
+++ b/policyengine_us/tests/policy/baseline/gov/states/wa/hca/apple_health/expansion/eligibility/wa_apple_health_expansion_immigration_status_eligible.yaml
@@ -0,0 +1,49 @@
+# Tests for Washington Apple Health Expansion immigration status eligibility
+
+- name: Undocumented immigrant is eligible
+  period: 2025
+  input:
+    immigration_status: UNDOCUMENTED
+    state_code: WA
+  output:
+    wa_apple_health_expansion_immigration_status_eligible: true
+
+- name: US citizen NOT eligible
+  period: 2025
+  input:
+    immigration_status: CITIZEN
+    state_code: WA
+  output:
+    wa_apple_health_expansion_immigration_status_eligible: false
+
+- name: Legal permanent resident NOT eligible
+  period: 2025
+  input:
+    immigration_status: LEGAL_PERMANENT_RESIDENT
+    state_code: WA
+  output:
+    wa_apple_health_expansion_immigration_status_eligible: false
+
+- name: Refugee NOT eligible (can access federal programs)
+  period: 2025
+  input:
+    immigration_status: REFUGEE
+    state_code: WA
+  output:
+    wa_apple_health_expansion_immigration_status_eligible: false
+
+- name: DACA recipient NOT eligible (pending HCA clarification)
+  period: 2025
+  input:
+    immigration_status: DACA
+    state_code: WA
+  output:
+    wa_apple_health_expansion_immigration_status_eligible: false
+
+- name: TPS recipient NOT eligible
+  period: 2025
+  input:
+    immigration_status: TPS
+    state_code: WA
+  output:
+    wa_apple_health_expansion_immigration_status_eligible: false
diff --git a/policyengine_us/tests/policy/baseline/gov/states/wa/hca/apple_health/expansion/eligibility/wa_apple_health_expansion_income_eligible.yaml b/policyengine_us/tests/policy/baseline/gov/states/wa/hca/apple_health/expansion/eligibility/wa_apple_health_expansion_income_eligible.yaml
new file mode 100644
index 00000000000..31159ee1d94
--- /dev/null
+++ b/policyengine_us/tests/policy/baseline/gov/states/wa/hca/apple_health/expansion/eligibility/wa_apple_health_expansion_income_eligible.yaml
@@ -0,0 +1,33 @@
+# Tests for Washington Apple Health Expansion income eligibility
+
+- name: Income at 100% FPL is eligible
+  period: 2025
+  input:
+    medicaid_income_level: 1.0
+    state_code: WA
+  output:
+    wa_apple_health_expansion_income_eligible: true
+
+- name: Income at 138% FPL is eligible (at limit)
+  period: 2025
+  input:
+    medicaid_income_level: 1.38
+    state_code: WA
+  output:
+    wa_apple_health_expansion_income_eligible: true
+
+- name: Income at 139% FPL is NOT eligible
+  period: 2025
+  input:
+    medicaid_income_level: 1.39
+    state_code: WA
+  output:
+    wa_apple_health_expansion_income_eligible: false
+
+- name: Income at 150% FPL is NOT eligible
+  period: 2025
+  input:
+    medicaid_income_level: 1.5
+    state_code: WA
+  output:
+    wa_apple_health_expansion_income_eligible: false
diff --git a/policyengine_us/tests/policy/baseline/gov/states/wa/hca/apple_health/integration.yaml b/policyengine_us/tests/policy/baseline/gov/states/wa/hca/apple_health/integration.yaml
new file mode 100644
index 00000000000..3f5de1c97fb
--- /dev/null
+++ b/policyengine_us/tests/policy/baseline/gov/states/wa/hca/apple_health/integration.yaml
@@ -0,0 +1,51 @@
+# Integration tests for Washington Apple Health
+# These state-funded programs are for people NOT eligible for federal Medicaid
+
+- name: Undocumented child eligible for Apple Health Kids but NOT federal Medicaid
+  period: 2024
+  input:
+    age: 10
+    immigration_status: UNDOCUMENTED
+    medicaid_income_level: 2.0  # 200% FPL
+    state_code: WA
+  output:
+    wa_apple_health_kids_eligible: true
+    is_medicaid_eligible: false
+    wa_apple_health_group: CHILD
+
+- name: Undocumented adult eligible for Expansion but NOT federal Medicaid
+  period: 2025
+  input:
+    age: 30
+    immigration_status: UNDOCUMENTED
+    is_pregnant: false
+    medicaid_income_level: 1.0  # 100% FPL
+    state_code: WA
+  output:
+    wa_apple_health_expansion_eligible: true
+    is_medicaid_eligible: false
+    wa_apple_health_group: EXPANSION_ADULT
+
+- name: US citizen child eligible through BOTH Apple Health Kids AND federal Medicaid
+  period: 2024
+  input:
+    age: 10
+    immigration_status: CITIZEN
+    medicaid_income_level: 1.0  # 100% FPL
+    state_code: WA
+  output:
+    wa_apple_health_kids_eligible: true
+    is_medicaid_eligible: true
+
+- name: Undocumented adult above income limit NOT eligible for any program
+  period: 2025
+  input:
+    age: 30
+    immigration_status: UNDOCUMENTED
+    is_pregnant: false
+    medicaid_income_level: 2.0  # 200% FPL (above 138% limit for Expansion)
+    state_code: WA
+  output:
+    wa_apple_health_expansion_eligible: false
+    wa_apple_health_kids_eligible: false
+    is_medicaid_eligible: false
diff --git a/policyengine_us/tests/policy/baseline/gov/states/wa/hca/apple_health/kids/eligibility/wa_apple_health_kids_eligible.yaml b/policyengine_us/tests/policy/baseline/gov/states/wa/hca/apple_health/kids/eligibility/wa_apple_health_kids_eligible.yaml
new file mode 100644
index 00000000000..26a8dbf52ab
--- /dev/null
+++ b/policyengine_us/tests/policy/baseline/gov/states/wa/hca/apple_health/kids/eligibility/wa_apple_health_kids_eligible.yaml
@@ -0,0 +1,83 @@
+# Tests for Washington Apple Health for Kids eligibility
+
+- name: Child under 19 with low income eligible
+  period: 2024
+  input:
+    age: 10
+    medicaid_income_level: 1.5  # 150% FPL
+    state_code: WA
+  output:
+    wa_apple_health_kids_eligible: true
+
+- name: Child at Tier 1 income level eligible
+  period: 2024
+  input:
+    age: 15
+    medicaid_income_level: 2.5  # 250% FPL (between 210% and 265%)
+    state_code: WA
+  output:
+    wa_apple_health_kids_eligible: true
+
+- name: Child at Tier 2 income level eligible
+  period: 2024
+  input:
+    age: 8
+    medicaid_income_level: 3.0  # 300% FPL (between 265% and 317%)
+    state_code: WA
+  output:
+    wa_apple_health_kids_eligible: true
+
+- name: Child at exactly 317% FPL eligible
+  period: 2024
+  input:
+    age: 12
+    medicaid_income_level: 3.17  # 317% FPL (at limit)
+    state_code: WA
+  output:
+    wa_apple_health_kids_eligible: true
+
+- name: Child with income above 317% FPL NOT eligible
+  period: 2024
+  input:
+    age: 10
+    medicaid_income_level: 3.5  # 350% FPL (above limit)
+    state_code: WA
+  output:
+    wa_apple_health_kids_eligible: false
+
+- name: Adult NOT eligible regardless of income
+  period: 2024
+  input:
+    age: 25
+    medicaid_income_level: 1.0  # 100% FPL
+    state_code: WA
+  output:
+    wa_apple_health_kids_eligible: false
+
+- name: 18-year-old still eligible (under 19)
+  period: 2024
+  input:
+    age: 18
+    medicaid_income_level: 2.0  # 200% FPL
+    state_code: WA
+  output:
+    wa_apple_health_kids_eligible: true
+
+- name: 19-year-old NOT eligible
+  period: 2024
+  input:
+    age: 19
+    medicaid_income_level: 1.0  # 100% FPL
+    state_code: WA
+  output:
+    wa_apple_health_kids_eligible: false
+
+- name: Undocumented child eligible (covers all immigration statuses)
+  period: 2024
+  input:
+    age: 10
+    immigration_status: UNDOCUMENTED
+    medicaid_income_level: 2.0  # 200% FPL
+    state_code: WA
+  output:
+    wa_apple_health_kids_eligible: true
diff --git a/policyengine_us/tests/policy/baseline/gov/states/wa/hca/apple_health/kids/eligibility/wa_apple_health_kids_income_eligible.yaml b/policyengine_us/tests/policy/baseline/gov/states/wa/hca/apple_health/kids/eligibility/wa_apple_health_kids_income_eligible.yaml
new file mode 100644
index 00000000000..7c0bd556fe8
--- /dev/null
+++ b/policyengine_us/tests/policy/baseline/gov/states/wa/hca/apple_health/kids/eligibility/wa_apple_health_kids_income_eligible.yaml
@@ -0,0 +1,49 @@
+# Tests for Washington Apple Health for Kids income eligibility
+
+- name: Income at 150% FPL is eligible (free tier)
+  period: 2024
+  input:
+    medicaid_income_level: 1.5
+    state_code: WA
+  output:
+    wa_apple_health_kids_income_eligible: true
+
+- name: Income at 215% FPL is eligible (free tier boundary with 5pp disregard)
+  period: 2024
+  input:
+    medicaid_income_level: 2.15
+    state_code: WA
+  output:
+    wa_apple_health_kids_income_eligible: true
+
+- name: Income at 265% FPL is eligible (Tier 1 boundary)
+  period: 2024
+  input:
+    medicaid_income_level: 2.65
+    state_code: WA
+  output:
+    wa_apple_health_kids_income_eligible: true
+
+- name: Income at 317% FPL is eligible (Tier 2 maximum)
+  period: 2024
+  input:
+    medicaid_income_level: 3.17
+    state_code: WA
+  output:
+    wa_apple_health_kids_income_eligible: true
+
+- name: Income at 318% FPL is NOT eligible
+  period: 2024
+  input:
+    medicaid_income_level: 3.18
+    state_code: WA
+  output:
+    wa_apple_health_kids_income_eligible: false
+
+- name: Income at 400% FPL is NOT eligible
+  period: 2024
+  input:
+    medicaid_income_level: 4.0
+    state_code: WA
+  output:
+    wa_apple_health_kids_income_eligible: false
diff --git a/policyengine_us/variables/gov/states/wa/hca/apple_health/costs/wa_apple_health_cost_if_enrolled.py b/policyengine_us/variables/gov/states/wa/hca/apple_health/costs/wa_apple_health_cost_if_enrolled.py
new file mode 100644
index 00000000000..8d175e61ae3
--- /dev/null
+++ b/policyengine_us/variables/gov/states/wa/hca/apple_health/costs/wa_apple_health_cost_if_enrolled.py
@@ -0,0 +1,57 @@
+from policyengine_us.model_api import *
+from policyengine_us.variables.gov.hhs.medicaid.costs.medicaid_group import (
+    MedicaidGroup,
+)
+
+
+class wa_apple_health_cost_if_enrolled(Variable):
+    value_type = float
+    entity = Person
+    label = "Per capita Washington Apple Health cost by eligibility group"
+    unit = USD
+    definition_period = YEAR
+    defined_for = StateCode.WA
+    reference = [
+        "https://www.hca.wa.gov/about-hca/programs-and-initiatives/apple-health-medicaid/apple-health-expansion",
+    ]
+    documentation = """
+    Calculates the per-capita cost of Washington Apple Health coverage based
+    on the person's eligibility group (Kids or Expansion). Uses Washington
+    state Medicaid cost data by eligibility category.
+
+    Note: Apple Health Expansion is 100% state-funded (~$150M in 2025-2027
+    biennial budget), while Apple Health for Kids uses a mix of state and
+    federal funds depending on the child's citizenship/immigration status.
+    """
+
+    def formula(person, period, parameters):
+        group = person("wa_apple_health_group", period)
+
+        p = parameters(period).calibration.gov.hhs.medicaid
+
+        is_child = group == MedicaidGroup.CHILD
+        is_expansion_adult = group == MedicaidGroup.EXPANSION_ADULT
+
+        # Use Washington state Medicaid cost data
+        child_spend = p.spending.by_eligibility_group.child["WA"]
+        expansion_adult_spend = (
+            p.spending.by_eligibility_group.expansion_adults["WA"]
+        )
+
+        child_enroll = p.enrollment.child["WA"]
+        expansion_adult_enroll = p.enrollment.expansion_adults["WA"]
+
+        spend = select(
+            [is_child, is_expansion_adult],
+            [child_spend, expansion_adult_spend],
+            default=0,
+        )
+
+        enroll = select(
+            [is_child, is_expansion_adult],
+            [child_enroll, expansion_adult_enroll],
+            default=0,
+        )
+
+        # Calculate per-capita cost, avoiding divide-by-zero
+        return np.where(enroll > 0, spend / enroll, 0)
diff --git a/policyengine_us/variables/gov/states/wa/hca/apple_health/costs/wa_apple_health_group.py b/policyengine_us/variables/gov/states/wa/hca/apple_health/costs/wa_apple_health_group.py
new file mode 100644
index 00000000000..7ec372ff96e
--- /dev/null
+++ b/policyengine_us/variables/gov/states/wa/hca/apple_health/costs/wa_apple_health_group.py
@@ -0,0 +1,42 @@
+from policyengine_us.model_api import *
+from policyengine_us.variables.gov.hhs.medicaid.costs.medicaid_group import (
+    MedicaidGroup,
+)
+
+
+class wa_apple_health_group(Variable):
+    """Maps Washington Apple Health eligibility to Medicaid spending groups.
+
+    Apple Health for Kids → CHILD
+    Apple Health Expansion → EXPANSION_ADULT
+    """
+
+    value_type = Enum
+    possible_values = MedicaidGroup
+    default_value = MedicaidGroup.NONE
+    entity = Person
+    label = "Washington Apple Health spending group"
+    definition_period = YEAR
+    defined_for = StateCode.WA
+    reference = [
+        "https://www.hca.wa.gov/free-or-low-cost-health-care/i-need-medical-dental-or-vision-care/children",
+        "https://www.hca.wa.gov/about-hca/programs-and-initiatives/apple-health-medicaid/apple-health-expansion",
+    ]
+
+    def formula(person, period, parameters):
+        kids_eligible = person("wa_apple_health_kids_eligible", period)
+        expansion_eligible = person(
+            "wa_apple_health_expansion_eligible", period
+        )
+
+        return select(
+            [
+                kids_eligible,
+                expansion_eligible,
+            ],
+            [
+                MedicaidGroup.CHILD,
+                MedicaidGroup.EXPANSION_ADULT,
+            ],
+            default=MedicaidGroup.NONE,
+        )
diff --git a/policyengine_us/variables/gov/states/wa/hca/apple_health/expansion/eligibility/wa_apple_health_expansion_eligible.py b/policyengine_us/variables/gov/states/wa/hca/apple_health/expansion/eligibility/wa_apple_health_expansion_eligible.py
new file mode 100644
index 00000000000..f4b15abca9b
--- /dev/null
+++ b/policyengine_us/variables/gov/states/wa/hca/apple_health/expansion/eligibility/wa_apple_health_expansion_eligible.py
@@ -0,0 +1,58 @@
+from policyengine_us.model_api import *
+
+
+class wa_apple_health_expansion_eligible(Variable):
+    value_type = bool
+    entity = Person
+    label = "Eligible for Washington Apple Health Expansion"
+    definition_period = YEAR
+    defined_for = StateCode.WA
+    reference = [
+        "https://app.leg.wa.gov/wac/default.aspx?cite=182-525-0300",
+        "https://www.hca.wa.gov/about-hca/programs-and-initiatives/apple-health-medicaid/apple-health-expansion",
+    ]
+    documentation = """
+    Washington Apple Health Expansion provides state-funded coverage for
+    adults age 19+ who are ineligible for federally funded Medicaid or
+    QHPs with APTC due to immigration status. Income limit is 138% FPL.
+
+    Note: This program has an enrollment cap and is not an entitlement.
+    Enrollment closed within 48 hours of launch on June 21, 2024.
+    The cap is not modeled here.
+
+    Exclusions:
+    - Pregnant individuals (must use pregnancy programs)
+    - Qualified immigrants in 5-year bar
+    - DACA recipients (status unclear as of January 2026)
+    """
+
+    def formula(person, period, parameters):
+        p = parameters(period).gov.states.wa.hca.apple_health.expansion
+
+        # Program must be in effect (launched June 21, 2024)
+        in_effect = p.eligibility.in_effect
+
+        # Must be adult (19+)
+        age = person("age", period)
+        age_eligible = age >= p.eligibility.min_age
+
+        # Must meet income requirements
+        income_eligible = person(
+            "wa_apple_health_expansion_income_eligible", period
+        )
+
+        # Must have eligible immigration status
+        immigration_eligible = person(
+            "wa_apple_health_expansion_immigration_status_eligible", period
+        )
+
+        # Must not be pregnant (pregnant individuals use pregnancy programs)
+        is_pregnant = person("is_pregnant", period)
+
+        return (
+            in_effect
+            & age_eligible
+            & income_eligible
+            & immigration_eligible
+            & ~is_pregnant
+        )
diff --git a/policyengine_us/variables/gov/states/wa/hca/apple_health/expansion/eligibility/wa_apple_health_expansion_immigration_status_eligible.py b/policyengine_us/variables/gov/states/wa/hca/apple_health/expansion/eligibility/wa_apple_health_expansion_immigration_status_eligible.py
new file mode 100644
index 00000000000..83603c8430a
--- /dev/null
+++ b/policyengine_us/variables/gov/states/wa/hca/apple_health/expansion/eligibility/wa_apple_health_expansion_immigration_status_eligible.py
@@ -0,0 +1,54 @@
+from policyengine_us.model_api import *
+
+
+class wa_apple_health_expansion_immigration_status_eligible(Variable):
+    value_type = bool
+    entity = Person
+    label = (
+        "Has eligible immigration status for Washington Apple Health Expansion"
+    )
+    definition_period = YEAR
+    defined_for = StateCode.WA
+    reference = [
+        "https://app.leg.wa.gov/wac/default.aspx?cite=182-525-0300",
+        "https://www.hca.wa.gov/about-hca/programs-and-initiatives/apple-health-medicaid/apple-health-expansion",
+    ]
+    documentation = """
+    Washington Apple Health Expansion covers adults who are NOT eligible for
+    federally funded Medicaid or QHPs with APTC due to immigration status.
+
+    Eligible immigration statuses:
+    - Undocumented immigrants
+
+    Excluded:
+    - U.S. citizens (eligible for regular Medicaid/QHPs)
+    - Lawfully present immigrants (eligible for regular Medicaid/QHPs)
+    - Qualified immigrants in 5-year bar (must use other programs)
+    - DACA recipients: Status unclear as of January 2026. After Trump admin
+      rule (effective August 25, 2025), DACA recipients lost federal ACA
+      subsidies but can still use Washington Healthplanfinder with state
+      Cascade Care Savings subsidies. HCA has not clarified if they are
+      now eligible for Apple Health Expansion. Excluding for now.
+    """
+
+    def formula(person, period, parameters):
+        immigration_status = person("immigration_status", period)
+
+        # Only undocumented immigrants are eligible
+        # They are ineligible for federal Medicaid and federal ACA subsidies
+        undocumented = (
+            immigration_status
+            == immigration_status.possible_values.UNDOCUMENTED
+        )
+
+        # NOTE: Qualified immigrants in the federal 5-year bar (e.g., LPRs
+        # who've been in the US less than 5 years) are technically excluded
+        # per WAC 182-525-0300. However, we don't currently track years_in_us
+        # or immigration entry date. These individuals would need to self-
+        # identify their eligibility. A future enhancement could add a
+        # years_in_us input variable to properly model the 5-year bar.
+
+        # DACA recipients excluded pending HCA clarification
+        # They may have access to Cascade Care Savings on state exchange
+
+        return undocumented
diff --git a/policyengine_us/variables/gov/states/wa/hca/apple_health/expansion/eligibility/wa_apple_health_expansion_income_eligible.py b/policyengine_us/variables/gov/states/wa/hca/apple_health/expansion/eligibility/wa_apple_health_expansion_income_eligible.py
new file mode 100644
index 00000000000..749e82ef7f7
--- /dev/null
+++ b/policyengine_us/variables/gov/states/wa/hca/apple_health/expansion/eligibility/wa_apple_health_expansion_income_eligible.py
@@ -0,0 +1,28 @@
+from policyengine_us.model_api import *
+
+
+class wa_apple_health_expansion_income_eligible(Variable):
+    value_type = bool
+    entity = Person
+    label = "Meets Washington Apple Health Expansion income eligibility"
+    definition_period = YEAR
+    defined_for = StateCode.WA
+    reference = [
+        "https://app.leg.wa.gov/wac/default.aspx?cite=182-525-0300",
+        "https://www.hca.wa.gov/assets/free-or-low-cost/income-standards.pdf",
+    ]
+    documentation = """
+    Washington Apple Health Expansion uses MAGI-based income at or below
+    138% FPL. The 5% disregard is already built into the threshold.
+    """
+
+    def formula(person, period, parameters):
+        p = parameters(
+            period
+        ).gov.states.wa.hca.apple_health.expansion.eligibility
+
+        # Use MAGI-based income level (as fraction of FPL)
+        income_level = person("medicaid_income_level", period)
+
+        # Eligible if at or below 138% FPL
+        return income_level <= p.income_limit
diff --git a/policyengine_us/variables/gov/states/wa/hca/apple_health/kids/eligibility/wa_apple_health_kids_eligible.py b/policyengine_us/variables/gov/states/wa/hca/apple_health/kids/eligibility/wa_apple_health_kids_eligible.py
new file mode 100644
index 00000000000..3b2ef6c6587
--- /dev/null
+++ b/policyengine_us/variables/gov/states/wa/hca/apple_health/kids/eligibility/wa_apple_health_kids_eligible.py
@@ -0,0 +1,38 @@
+from policyengine_us.model_api import *
+
+
+class wa_apple_health_kids_eligible(Variable):
+    value_type = bool
+    entity = Person
+    label = "Eligible for Washington Apple Health for Kids"
+    definition_period = YEAR
+    defined_for = StateCode.WA
+    reference = [
+        "https://app.leg.wa.gov/rcw/default.aspx?cite=74.09.470",
+        "https://www.hca.wa.gov/free-or-low-cost-health-care/i-need-medical-dental-or-vision-care/children",
+    ]
+    documentation = """
+    Washington Apple Health for Kids provides state-funded Medicaid/CHIP
+    coverage for children under 19 regardless of immigration status.
+    Coverage is available at different premium tiers based on income.
+    """
+
+    def formula(person, period, parameters):
+        p = parameters(period).gov.states.wa.hca.apple_health.kids
+
+        # Program must be in effect
+        in_effect = p.eligibility.in_effect
+
+        # Must be under age limit (19)
+        age = person("age", period)
+        age_eligible = age < p.eligibility.age_limit
+
+        # Must meet income requirements
+        income_eligible = person(
+            "wa_apple_health_kids_income_eligible", period
+        )
+
+        # Washington covers children regardless of immigration status
+        # No immigration status check needed
+
+        return in_effect & age_eligible & income_eligible
diff --git a/policyengine_us/variables/gov/states/wa/hca/apple_health/kids/eligibility/wa_apple_health_kids_income_eligible.py b/policyengine_us/variables/gov/states/wa/hca/apple_health/kids/eligibility/wa_apple_health_kids_income_eligible.py
new file mode 100644
index 00000000000..173490fcdd4
--- /dev/null
+++ b/policyengine_us/variables/gov/states/wa/hca/apple_health/kids/eligibility/wa_apple_health_kids_income_eligible.py
@@ -0,0 +1,27 @@
+from policyengine_us.model_api import *
+
+
+class wa_apple_health_kids_income_eligible(Variable):
+    value_type = bool
+    entity = Person
+    label = "Meets Washington Apple Health for Kids income eligibility"
+    definition_period = YEAR
+    defined_for = StateCode.WA
+    reference = [
+        "https://app.leg.wa.gov/wac/default.aspx?cite=182-505-0100",
+        "https://www.hca.wa.gov/assets/free-or-low-cost/income-standards.pdf",
+    ]
+    documentation = """
+    Washington Apple Health for Kids uses MAGI-based income with the 5%
+    disregard already built into published thresholds. Maximum eligibility
+    is at 317% FPL.
+    """
+
+    def formula(person, period, parameters):
+        p = parameters(period).gov.states.wa.hca.apple_health.kids.income_limit
+
+        # Use MAGI-based income level (as fraction of FPL)
+        income_level = person("medicaid_income_level", period)
+
+        # Eligible if at or below Tier 2 maximum (317% FPL)
+        return income_level <= p.tier_2
diff --git a/uv.lock b/uv.lock
index 06bf5cb6b5b..551b0a0dce1 100644
--- a/uv.lock
+++ b/uv.lock
@@ -718,7 +718,7 @@ name = "importlib-metadata"
 version = "8.7.1"
 source = { registry = "https://pypi.org/simple" }
 dependencies = [
-    { name = "zipp" },
+    { name = "zipp", marker = "python_full_version < '3.11'" },
 ]
 sdist = { url = "https://files.pythonhosted.org/packages/f3/49/3b30cad09e7771a4982d9975a8cbf64f00d4a1ececb53297f1d9a7be1b10/importlib_metadata-8.7.1.tar.gz", hash = "sha256:49fef1ae6440c182052f407c8d34a68f72efc36db9ca90dc0113398f2fdde8bb", size = 57107, upload-time = "2025-12-21T10:00:19.278Z" }
 wheels = [
@@ -1535,7 +1535,7 @@ wheels = [
 
 [[package]]
 name = "policyengine-us"
-version = "1.485.0"
+version = "1.496.2"
 source = { editable = "." }
 dependencies = [
     { name = "microdf-python" },