diff --git a/changelog.d/issue-8136-wa-pfml.added.md b/changelog.d/issue-8136-wa-pfml.added.md
new file mode 100644
index 00000000000..bee359f9567
--- /dev/null
+++ b/changelog.d/issue-8136-wa-pfml.added.md
@@ -0,0 +1 @@
+Add a Washington Paid Family and Medical Leave eligibility and maximum benefit calculator.
diff --git a/policyengine_us/parameters/gov/states/wa/pfml/duration/combined_max_weeks.yaml b/policyengine_us/parameters/gov/states/wa/pfml/duration/combined_max_weeks.yaml
new file mode 100644
index 00000000000..fe7adca840d
--- /dev/null
+++ b/policyengine_us/parameters/gov/states/wa/pfml/duration/combined_max_weeks.yaml
@@ -0,0 +1,12 @@
+description: Washington limits combined family and medical leave to this number of weeks under the Paid Family and Medical Leave program.
+
+values:
+  2020-01-01: 16
+
+metadata:
+  unit: week
+  period: year
+  label: Washington PFML combined leave maximum weeks
+  reference:
+    - title: RCW 50A.15.020(3)(c) Benefit—Amount and duration
+      href: https://app.leg.wa.gov/rcw/default.aspx?cite=50A.15.020
diff --git a/policyengine_us/parameters/gov/states/wa/pfml/duration/combined_max_weeks_with_pregnancy_incapacity.yaml b/policyengine_us/parameters/gov/states/wa/pfml/duration/combined_max_weeks_with_pregnancy_incapacity.yaml
new file mode 100644
index 00000000000..775f8858b3b
--- /dev/null
+++ b/policyengine_us/parameters/gov/states/wa/pfml/duration/combined_max_weeks_with_pregnancy_incapacity.yaml
@@ -0,0 +1,12 @@
+description: Washington limits combined family and medical leave to this number of weeks when a serious health condition with pregnancy results in incapacity under the Paid Family and Medical Leave program.
+
+values:
+  2020-01-01: 18
+
+metadata:
+  unit: week
+  period: year
+  label: Washington PFML combined leave maximum weeks with pregnancy incapacity
+  reference:
+    - title: RCW 50A.15.020(3)(c) Benefit—Amount and duration
+      href: https://app.leg.wa.gov/rcw/default.aspx?cite=50A.15.020
diff --git a/policyengine_us/parameters/gov/states/wa/pfml/duration/family_leave_weeks.yaml b/policyengine_us/parameters/gov/states/wa/pfml/duration/family_leave_weeks.yaml
new file mode 100644
index 00000000000..8398c594937
--- /dev/null
+++ b/policyengine_us/parameters/gov/states/wa/pfml/duration/family_leave_weeks.yaml
@@ -0,0 +1,12 @@
+description: Washington limits family leave to this number of weeks under the Paid Family and Medical Leave program.
+
+values:
+  2020-01-01: 12
+
+metadata:
+  unit: week
+  period: year
+  label: Washington PFML family leave maximum weeks
+  reference:
+    - title: RCW 50A.15.020(3)(a) Benefit—Amount and duration
+      href: https://app.leg.wa.gov/rcw/default.aspx?cite=50A.15.020
diff --git a/policyengine_us/parameters/gov/states/wa/pfml/duration/medical_leave_weeks.yaml b/policyengine_us/parameters/gov/states/wa/pfml/duration/medical_leave_weeks.yaml
new file mode 100644
index 00000000000..9e9ee1d6416
--- /dev/null
+++ b/policyengine_us/parameters/gov/states/wa/pfml/duration/medical_leave_weeks.yaml
@@ -0,0 +1,12 @@
+description: Washington limits medical leave to this number of weeks under the Paid Family and Medical Leave program.
+
+values:
+  2020-01-01: 12
+
+metadata:
+  unit: week
+  period: year
+  label: Washington PFML medical leave maximum weeks
+  reference:
+    - title: RCW 50A.15.020(3)(b) Benefit—Amount and duration
+      href: https://app.leg.wa.gov/rcw/default.aspx?cite=50A.15.020
diff --git a/policyengine_us/parameters/gov/states/wa/pfml/duration/medical_leave_weeks_with_pregnancy_incapacity.yaml b/policyengine_us/parameters/gov/states/wa/pfml/duration/medical_leave_weeks_with_pregnancy_incapacity.yaml
new file mode 100644
index 00000000000..84e76298b05
--- /dev/null
+++ b/policyengine_us/parameters/gov/states/wa/pfml/duration/medical_leave_weeks_with_pregnancy_incapacity.yaml
@@ -0,0 +1,12 @@
+description: Washington limits medical leave to this number of weeks when a serious health condition with pregnancy results in incapacity under the Paid Family and Medical Leave program.
+
+values:
+  2020-01-01: 14
+
+metadata:
+  unit: week
+  period: year
+  label: Washington PFML medical leave maximum weeks with pregnancy incapacity
+  reference:
+    - title: RCW 50A.15.020(3)(b) Benefit—Amount and duration
+      href: https://app.leg.wa.gov/rcw/default.aspx?cite=50A.15.020
diff --git a/policyengine_us/parameters/gov/states/wa/pfml/hours_threshold.yaml b/policyengine_us/parameters/gov/states/wa/pfml/hours_threshold.yaml
new file mode 100644
index 00000000000..7a410479653
--- /dev/null
+++ b/policyengine_us/parameters/gov/states/wa/pfml/hours_threshold.yaml
@@ -0,0 +1,12 @@
+description: Washington requires this many hours worked in the qualifying period for eligibility under the Paid Family and Medical Leave program.
+
+values:
+  2020-01-01: 820
+
+metadata:
+  unit: hour
+  period: year
+  label: Washington PFML qualifying hours threshold
+  reference:
+    - title: RCW 50A.15.010 Employee eligibility
+      href: https://app.leg.wa.gov/rcw/default.aspx?cite=50A.15.010
diff --git a/policyengine_us/parameters/gov/states/wa/pfml/lower_benefit_rate.yaml b/policyengine_us/parameters/gov/states/wa/pfml/lower_benefit_rate.yaml
new file mode 100644
index 00000000000..e7cba1a2119
--- /dev/null
+++ b/policyengine_us/parameters/gov/states/wa/pfml/lower_benefit_rate.yaml
@@ -0,0 +1,12 @@
+description: Washington replaces this share of the employee's average weekly wage below the benefit tier threshold under the Paid Family and Medical Leave program.
+
+values:
+  2020-01-01: 0.9
+
+metadata:
+  unit: /1
+  period: year
+  label: Washington PFML lower tier benefit rate
+  reference:
+    - title: RCW 50A.15.020(5)(a) Benefit—Amount and duration
+      href: https://app.leg.wa.gov/rcw/default.aspx?cite=50A.15.020
diff --git a/policyengine_us/parameters/gov/states/wa/pfml/lower_threshold_fraction.yaml b/policyengine_us/parameters/gov/states/wa/pfml/lower_threshold_fraction.yaml
new file mode 100644
index 00000000000..3bf2c63f90d
--- /dev/null
+++ b/policyengine_us/parameters/gov/states/wa/pfml/lower_threshold_fraction.yaml
@@ -0,0 +1,12 @@
+description: Washington uses this share of the state average weekly wage as the breakpoint between benefit tiers under the Paid Family and Medical Leave program.
+
+values:
+  2020-01-01: 0.5
+
+metadata:
+  unit: /1
+  period: year
+  label: Washington PFML lower benefit tier threshold fraction
+  reference:
+    - title: RCW 50A.15.020(5) Benefit—Amount and duration
+      href: https://app.leg.wa.gov/rcw/default.aspx?cite=50A.15.020
diff --git a/policyengine_us/parameters/gov/states/wa/pfml/max_weekly_benefit_amount.yaml b/policyengine_us/parameters/gov/states/wa/pfml/max_weekly_benefit_amount.yaml
new file mode 100644
index 00000000000..a27d50e6e28
--- /dev/null
+++ b/policyengine_us/parameters/gov/states/wa/pfml/max_weekly_benefit_amount.yaml
@@ -0,0 +1,20 @@
+description: Washington limits the weekly benefit to this amount under the Paid Family and Medical Leave program.
+
+values:
+  2020-01-01: 1_000
+  2021-01-01: 1_206
+  2022-01-01: 1_327
+  2023-01-01: 1_427
+  2024-01-01: 1_456
+  2025-01-01: 1_542
+  2026-01-01: 1_647
+
+metadata:
+  unit: currency-USD
+  period: week
+  label: Washington PFML maximum weekly benefit amount
+  reference:
+    - title: RCW 50A.15.020(6)(a) Benefit—Amount and duration
+      href: https://app.leg.wa.gov/rcw/default.aspx?cite=50A.15.020
+    - title: Washington Paid Family and Medical Leave 2026 Paycheck Insert
+      href: https://paidleave.wa.gov/app/uploads/2025/12/Paycheck-insert-2026-1.pdf
diff --git a/policyengine_us/parameters/gov/states/wa/pfml/min_weekly_benefit_amount.yaml b/policyengine_us/parameters/gov/states/wa/pfml/min_weekly_benefit_amount.yaml
new file mode 100644
index 00000000000..3971b2b39c1
--- /dev/null
+++ b/policyengine_us/parameters/gov/states/wa/pfml/min_weekly_benefit_amount.yaml
@@ -0,0 +1,12 @@
+description: Washington sets the minimum weekly benefit to this amount under the Paid Family and Medical Leave program.
+
+values:
+  2020-01-01: 100
+
+metadata:
+  unit: currency-USD
+  period: week
+  label: Washington PFML minimum weekly benefit amount
+  reference:
+    - title: RCW 50A.15.020(6)(b) Benefit—Amount and duration
+      href: https://app.leg.wa.gov/rcw/default.aspx?cite=50A.15.020
diff --git a/policyengine_us/parameters/gov/states/wa/pfml/state_average_weekly_wage.yaml b/policyengine_us/parameters/gov/states/wa/pfml/state_average_weekly_wage.yaml
new file mode 100644
index 00000000000..b6235e0fe30
--- /dev/null
+++ b/policyengine_us/parameters/gov/states/wa/pfml/state_average_weekly_wage.yaml
@@ -0,0 +1,22 @@
+description: Washington uses this state average weekly wage to determine weekly benefits under the Paid Family and Medical Leave program.
+
+values:
+  2020-01-01: 1_111
+  2021-01-01: 1_340
+  2022-01-01: 1_474
+  2023-01-01: 1_586
+  2024-01-01: 1_618
+  2025-01-01: 1_714
+  2026-01-01: 1_830
+
+metadata:
+  unit: currency-USD
+  period: week
+  label: Washington PFML state average weekly wage
+  reference:
+    - title: RCW 50A.05.010(26) State average weekly wage
+      href: https://app.leg.wa.gov/rcw/default.aspx?cite=50A.05.010
+    - title: RCW 50A.15.020(6)(a) Benefit—Amount and duration
+      href: https://app.leg.wa.gov/rcw/default.aspx?cite=50A.15.020
+    - title: Washington Paid Family and Medical Leave 2026 Paycheck Insert
+      href: https://paidleave.wa.gov/app/uploads/2025/12/Paycheck-insert-2026-1.pdf
diff --git a/policyengine_us/parameters/gov/states/wa/pfml/upper_benefit_rate.yaml b/policyengine_us/parameters/gov/states/wa/pfml/upper_benefit_rate.yaml
new file mode 100644
index 00000000000..42de004e4ff
--- /dev/null
+++ b/policyengine_us/parameters/gov/states/wa/pfml/upper_benefit_rate.yaml
@@ -0,0 +1,12 @@
+description: Washington replaces this share of the employee's average weekly wage above the benefit tier threshold under the Paid Family and Medical Leave program.
+
+values:
+  2020-01-01: 0.5
+
+metadata:
+  unit: /1
+  period: year
+  label: Washington PFML upper tier benefit rate
+  reference:
+    - title: RCW 50A.15.020(5)(b)(ii) Benefit—Amount and duration
+      href: https://app.leg.wa.gov/rcw/default.aspx?cite=50A.15.020
diff --git a/policyengine_us/tests/policy/baseline/gov/states/wa/pfml/test_wa_pfml.yaml b/policyengine_us/tests/policy/baseline/gov/states/wa/pfml/test_wa_pfml.yaml
new file mode 100644
index 00000000000..09febab4c17
--- /dev/null
+++ b/policyengine_us/tests/policy/baseline/gov/states/wa/pfml/test_wa_pfml.yaml
@@ -0,0 +1,114 @@
+- name: Case 1, eligible worker with combined leave facts gets the maximum annual benefit.
+  period: 2026
+  input:
+    people:
+      person1:
+        weekly_hours_worked: 20
+        employment_income: 52_000
+        wa_pfml_leave_type: COMBINED
+    households:
+      household:
+        members: [person1]
+        state_code: WA
+  output:
+    wa_pfml_eligible: true
+    wa_pfml_weekly_benefit_amount: 866
+    wa_pfml_max_leave_weeks: 16
+    wa_pfml: 13_856
+
+- name: Case 2, no leave type selected produces no maximum benefit estimate.
+  period: 2026
+  input:
+    people:
+      person1:
+        weekly_hours_worked: 20
+        employment_income: 52_000
+    households:
+      household:
+        members: [person1]
+        state_code: WA
+  output:
+    wa_pfml_eligible: true
+    wa_pfml_max_leave_weeks: 0
+    wa_pfml: 0
+
+- name: Case 3, family leave estimate uses the 12 week cap.
+  period: 2026
+  input:
+    people:
+      person1:
+        weekly_hours_worked: 20
+        employment_income: 52_000
+        wa_pfml_leave_type: FAMILY
+    households:
+      household:
+        members: [person1]
+        state_code: WA
+  output:
+    wa_pfml_max_leave_weeks: 12
+    wa_pfml: 10_392
+
+- name: Case 4, medical leave estimate uses the 12 week cap.
+  period: 2026
+  input:
+    people:
+      person1:
+        weekly_hours_worked: 20
+        employment_income: 52_000
+        wa_pfml_leave_type: MEDICAL
+    households:
+      household:
+        members: [person1]
+        state_code: WA
+  output:
+    wa_pfml_max_leave_weeks: 12
+    wa_pfml: 10_392
+
+- name: Case 5, pregnancy-related medical leave estimate uses the 14 week cap.
+  period: 2026
+  input:
+    people:
+      person1:
+        weekly_hours_worked: 20
+        employment_income: 52_000
+        wa_pfml_leave_type: MEDICAL_WITH_PREGNANCY_INCAPACITY
+    households:
+      household:
+        members: [person1]
+        state_code: WA
+  output:
+    wa_pfml_max_leave_weeks: 14
+    wa_pfml: 12_124
+
+- name: Case 6, combined leave with pregnancy incapacity estimate uses the 18 week cap.
+  period: 2026
+  input:
+    people:
+      person1:
+        weekly_hours_worked: 20
+        employment_income: 52_000
+        wa_pfml_leave_type: COMBINED_WITH_PREGNANCY_INCAPACITY
+    households:
+      household:
+        members: [person1]
+        state_code: WA
+  output:
+    wa_pfml_max_leave_weeks: 18
+    wa_pfml: 15_588
+
+- name: Case 7, ineligible workers get no leave or benefit estimate.
+  period: 2026
+  input:
+    people:
+      person1:
+        weekly_hours_worked: 15
+        employment_income: 52_000
+        wa_pfml_leave_type: COMBINED
+    households:
+      household:
+        members: [person1]
+        state_code: WA
+  output:
+    wa_pfml_eligible: false
+    wa_pfml_max_leave_weeks: 0
+    wa_pfml: 0
diff --git a/policyengine_us/tests/policy/baseline/gov/states/wa/pfml/test_wa_pfml_eligible.yaml b/policyengine_us/tests/policy/baseline/gov/states/wa/pfml/test_wa_pfml_eligible.yaml
new file mode 100644
index 00000000000..8a68b7e9219
--- /dev/null
+++ b/policyengine_us/tests/policy/baseline/gov/states/wa/pfml/test_wa_pfml_eligible.yaml
@@ -0,0 +1,59 @@
+- name: Case 1, non-Washington worker with sufficient hours is ineligible.
+  period: 2026
+  input:
+    state_code: CA
+    weekly_hours_worked: 20
+  output:
+    # Benefit only available to Washington workers (defined_for StateCode.WA).
+    wa_pfml_eligible: false
+
+- name: Case 2, part-time Washington worker below the hours threshold is ineligible.
+  period: 2026
+  input:
+    state_code: WA
+    weekly_hours_worked: 15
+  output:
+    # annual_hours = 15 * 52 = 780 hours
+    # 780 < 820 threshold per RCW 50A.15.010, so ineligible.
+    wa_pfml_eligible: false
+
+- name: Case 3, Washington worker just above the hours threshold is eligible.
+  period: 2026
+  input:
+    state_code: WA
+    weekly_hours_worked: 16
+  output:
+    # annual_hours = 16 * 52 = 832 hours
+    # 832 >= 820 threshold per RCW 50A.15.010, so eligible.
+    wa_pfml_eligible: true
+
+- name: Case 4, Washington worker with zero hours is ineligible.
+  period: 2026
+  input:
+    state_code: WA
+    weekly_hours_worked: 0
+  output:
+    # annual_hours = 0 < 820, so ineligible.
+    wa_pfml_eligible: false
+
+- name: Case 5, qualifying-period hours override can make a worker eligible.
+  period: 2026
+  input:
+    state_code: WA
+    weekly_hours_worked: 0
+    wa_pfml_qualifying_period_hours_worked: 900
+  output:
+    # Override replaces the weekly-hours proxy for eligibility.
+    # 900 >= 820 threshold, so eligible.
+    wa_pfml_eligible: true
+
+- name: Case 6, qualifying-period hours override takes precedence over weekly-hours proxy.
+  period: 2026
+  input:
+    state_code: WA
+    weekly_hours_worked: 20
+    wa_pfml_qualifying_period_hours_worked: 800
+  output:
+    # Override replaces the weekly-hours proxy for eligibility.
+    # 800 < 820 threshold, so ineligible.
+    wa_pfml_eligible: false
diff --git a/policyengine_us/tests/policy/baseline/gov/states/wa/pfml/test_wa_pfml_max_leave_weeks.yaml b/policyengine_us/tests/policy/baseline/gov/states/wa/pfml/test_wa_pfml_max_leave_weeks.yaml
new file mode 100644
index 00000000000..eccb2b21c35
--- /dev/null
+++ b/policyengine_us/tests/policy/baseline/gov/states/wa/pfml/test_wa_pfml_max_leave_weeks.yaml
@@ -0,0 +1,82 @@
+- name: Case 1, family leave is limited to 12 weeks.
+  period: 2026
+  input:
+    people:
+      person1:
+        weekly_hours_worked: 20
+        wa_pfml_leave_type: FAMILY
+    households:
+      household:
+        members: [person1]
+        state_code: WA
+  output:
+    wa_pfml_max_leave_weeks: 12
+
+- name: Case 2, medical leave is limited to 12 weeks.
+  period: 2026
+  input:
+    people:
+      person1:
+        weekly_hours_worked: 20
+        wa_pfml_leave_type: MEDICAL
+    households:
+      household:
+        members: [person1]
+        state_code: WA
+  output:
+    wa_pfml_max_leave_weeks: 12
+
+- name: Case 3, combined leave is limited to 16 weeks.
+  period: 2026
+  input:
+    people:
+      person1:
+        weekly_hours_worked: 20
+        wa_pfml_leave_type: COMBINED
+    households:
+      household:
+        members: [person1]
+        state_code: WA
+  output:
+    wa_pfml_max_leave_weeks: 16
+
+- name: Case 4, pregnancy-related medical leave is limited to 14 weeks.
+  period: 2026
+  input:
+    people:
+      person1:
+        weekly_hours_worked: 20
+        wa_pfml_leave_type: MEDICAL_WITH_PREGNANCY_INCAPACITY
+    households:
+      household:
+        members: [person1]
+        state_code: WA
+  output:
+    wa_pfml_max_leave_weeks: 14
+
+- name: Case 5, combined leave with pregnancy incapacity is limited to 18 weeks.
+  period: 2026
+  input:
+    people:
+      person1:
+        weekly_hours_worked: 20
+        wa_pfml_leave_type: COMBINED_WITH_PREGNANCY_INCAPACITY
+    households:
+      household:
+        members: [person1]
+        state_code: WA
+  output:
+    wa_pfml_max_leave_weeks: 18
+
+- name: Case 6, no selected leave type returns zero maximum leave weeks.
+  period: 2026
+  input:
+    people:
+      person1:
+        weekly_hours_worked: 20
+    households:
+      household:
+        members: [person1]
+        state_code: WA
+  output:
+    wa_pfml_max_leave_weeks: 0
diff --git a/policyengine_us/tests/policy/baseline/gov/states/wa/pfml/test_wa_pfml_weekly_benefit_amount.yaml b/policyengine_us/tests/policy/baseline/gov/states/wa/pfml/test_wa_pfml_weekly_benefit_amount.yaml
new file mode 100644
index 00000000000..d3aff64f0e8
--- /dev/null
+++ b/policyengine_us/tests/policy/baseline/gov/states/wa/pfml/test_wa_pfml_weekly_benefit_amount.yaml
@@ -0,0 +1,128 @@
+- name: Case 1, low earner below the SAWW breakpoint receives 90 percent of AWW.
+  period: 2026
+  input:
+    state_code: WA
+    employment_income: 26_000
+  output:
+    # AWW = 26,000 / 52 = 500
+    # SAWW 2026 = 1,830; breakpoint H = 0.5 * 1,830 = 915
+    # AWW (500) <= H (915), so benefit = 0.90 * 500 = 450
+    wa_pfml_weekly_benefit_amount: 450
+
+- name: Case 2, AWW exactly at the SAWW breakpoint.
+  period: 2026
+  input:
+    state_code: WA
+    employment_income: 47_580
+  output:
+    # AWW = 47,580 / 52 = 915
+    # AWW (915) <= H (915), so benefit = 0.90 * 915 = 823.50, rounded down to 823
+    wa_pfml_weekly_benefit_amount: 823
+
+- name: Case 3, AWW above the SAWW breakpoint uses two-tier formula.
+  period: 2026
+  input:
+    state_code: WA
+    employment_income: 78_000
+  output:
+    # AWW = 78,000 / 52 = 1,500
+    # AWW (1,500) > H (915), so benefit = 0.90 * 915 + 0.50 * (1,500 - 915)
+    # = 823.50 + 0.50 * 585
+    # = 823.50 + 292.50
+    # = 1,116
+    wa_pfml_weekly_benefit_amount: 1_116
+
+- name: Case 4, high earner with benefit capped at the maximum weekly benefit.
+  period: 2026
+  input:
+    state_code: WA
+    employment_income: 156_000
+  output:
+    # AWW = 156,000 / 52 = 3,000
+    # Raw = 0.90 * 915 + 0.50 * (3,000 - 915)
+    # = 823.50 + 0.50 * 2,085
+    # = 823.50 + 1,042.50
+    # = 1,866
+    # Max weekly benefit 2026 = 0.90 * 1,830 = 1,647
+    # Benefit = min(1,866, 1,647) = 1,647
+    wa_pfml_weekly_benefit_amount: 1_647
+
+- name: Case 5, AWW below 100 dollars returns full AWW per RCW 50A.15.020(6)(b).
+  period: 2026
+  input:
+    state_code: WA
+    employment_income: 4_160
+  output:
+    # AWW = 4,160 / 52 = 80
+    # AWW < 100 per RCW 50A.15.020(6)(b), so benefit = AWW = 80
+    # (not the 100 minimum; uses employee's full wage)
+    wa_pfml_weekly_benefit_amount: 80
+
+- name: Case 6, zero employment income produces zero benefit.
+  period: 2026
+  input:
+    state_code: WA
+    employment_income: 0
+  output:
+    # AWW = 0 / 52 = 0
+    # Per RCW 50A.15.020(6)(b), if AWW < 100 the benefit equals AWW;
+    # with no wages there is no benefit.
+    wa_pfml_weekly_benefit_amount: 0
+
+- name: Case 7, AWW one dollar below the SAWW breakpoint.
+  period: 2026
+  input:
+    state_code: WA
+    employment_income: 47_528
+  output:
+    # AWW = 47,528 / 52 = 914
+    # AWW (914) <= H (915), so benefit = 0.90 * 914 = 822.60, rounded down to 822
+    wa_pfml_weekly_benefit_amount: 822
+
+- name: Case 8, AWW one dollar above the SAWW breakpoint.
+  period: 2026
+  input:
+    state_code: WA
+    employment_income: 47_632
+  output:
+    # AWW = 47,632 / 52 = 916
+    # AWW (916) > H (915), so benefit = 0.90 * 915 + 0.50 * (916 - 915)
+    # = 823.50 + 0.50
+    # = 824.00, rounded down to 824
+    wa_pfml_weekly_benefit_amount: 824
+
+- name: Case 9, AWW exactly at the maximum weekly benefit threshold.
+  period: 2026
+  input:
+    state_code: WA
+    employment_income: 133_224
+  output:
+    # AWW = 133,224 / 52 = 2,562
+    # Raw = 0.90 * 915 + 0.50 * (2,562 - 915)
+    # = 823.50 + 0.50 * 1,647
+    # = 823.50 + 823.50
+    # = 1,647
+    # Equal to max weekly benefit (0.90 * 1,830 = 1,647), so benefit = 1,647
+    wa_pfml_weekly_benefit_amount: 1_647
+
+- name: Case 10, non-integer AWW is rounded down before applying the benefit formula.
+  period: 2026
+  input:
+    state_code: WA
+    employment_income: 47_579
+  output:
+    # Raw AWW approximation = 47,579 / 52 = 914.98...
+    # RCW 50A.05.010(6) rounds AWW down to the next lower dollar, so AWW = 914.
+    # Benefit = 0.90 * 914 = 822.60, rounded down to 822.
+    wa_pfml_weekly_benefit_amount: 822
+
+- name: Case 11, average weekly wage override replaces the annual-income proxy.
+  period: 2026
+  input:
+    state_code: WA
+    employment_income: 78_000
+    wa_pfml_average_weekly_wage_override: 800.75
+  output:
+    # Override AWW is rounded down to 800 before applying the formula.
+    # AWW (800) <= H (915), so benefit = 0.90 * 800 = 720.
+    wa_pfml_weekly_benefit_amount: 720
diff --git a/policyengine_us/variables/gov/states/wa/pfml/wa_pfml.py b/policyengine_us/variables/gov/states/wa/pfml/wa_pfml.py
new file mode 100644
index 00000000000..7596da1186f
--- /dev/null
+++ b/policyengine_us/variables/gov/states/wa/pfml/wa_pfml.py
@@ -0,0 +1,24 @@
+from policyengine_us.model_api import *
+
+
+class wa_pfml(Variable):
+    value_type = float
+    entity = Person
+    label = "Washington PFML maximum annual benefit"
+    documentation = (
+        "Maximum annual Washington Paid Family and Medical Leave benefit for "
+        "the selected leave type. Computed as the weekly benefit amount "
+        "multiplied by the maximum eligible leave duration."
+    )
+    unit = USD
+    definition_period = YEAR
+    defined_for = "wa_pfml_eligible"
+    reference = (
+        "https://app.leg.wa.gov/rcw/default.aspx?cite=50A.15.020",
+        "https://app.leg.wa.gov/rcw/default.aspx?cite=50A.15.010",
+    )
+
+    def formula(person, period, parameters):
+        weekly_benefit = person("wa_pfml_weekly_benefit_amount", period)
+        max_leave_weeks = person("wa_pfml_max_leave_weeks", period)
+        return weekly_benefit * max_leave_weeks
diff --git a/policyengine_us/variables/gov/states/wa/pfml/wa_pfml_average_weekly_wage.py b/policyengine_us/variables/gov/states/wa/pfml/wa_pfml_average_weekly_wage.py
new file mode 100644
index 00000000000..ba99bf46bcb
--- /dev/null
+++ b/policyengine_us/variables/gov/states/wa/pfml/wa_pfml_average_weekly_wage.py
@@ -0,0 +1,25 @@
+from policyengine_us.model_api import *
+
+
+class wa_pfml_average_weekly_wage(Variable):
+    value_type = float
+    entity = Person
+    label = "Washington PFML average weekly wage"
+    documentation = (
+        "Employee's average weekly wage for Washington Paid Family and "
+        "Medical Leave. Simplified as annual employment income divided by "
+        "the number of weeks in a year and rounded down to the next lower "
+        "dollar."
+    )
+    unit = USD
+    definition_period = YEAR
+    defined_for = StateCode.WA
+    reference = (
+        "https://app.leg.wa.gov/rcw/default.aspx?cite=50A.05.010",
+        "https://app.leg.wa.gov/rcw/default.aspx?cite=50A.15.020",
+    )
+
+    def formula(person, period, parameters):
+        override = person("wa_pfml_average_weekly_wage_override", period)
+        proxy_aww = np.floor(person("employment_income", period) / WEEKS_IN_YEAR)
+        return where(override >= 0, np.floor(override), proxy_aww)
diff --git a/policyengine_us/variables/gov/states/wa/pfml/wa_pfml_average_weekly_wage_override.py b/policyengine_us/variables/gov/states/wa/pfml/wa_pfml_average_weekly_wage_override.py
new file mode 100644
index 00000000000..52ddc2a0792
--- /dev/null
+++ b/policyengine_us/variables/gov/states/wa/pfml/wa_pfml_average_weekly_wage_override.py
@@ -0,0 +1,19 @@
+from policyengine_us.model_api import *
+
+
+class wa_pfml_average_weekly_wage_override(Variable):
+    value_type = float
+    entity = Person
+    label = "Washington PFML average weekly wage override"
+    documentation = (
+        "Optional override for Washington PFML average weekly wage. Set to a "
+        "non-negative dollar amount to replace the annual-income proxy."
+    )
+    unit = USD
+    definition_period = YEAR
+    defined_for = StateCode.WA
+    default_value = -1
+    reference = (
+        "https://app.leg.wa.gov/rcw/default.aspx?cite=50A.05.010",
+        "https://app.leg.wa.gov/rcw/default.aspx?cite=50A.15.020",
+    )
diff --git a/policyengine_us/variables/gov/states/wa/pfml/wa_pfml_eligible.py b/policyengine_us/variables/gov/states/wa/pfml/wa_pfml_eligible.py
new file mode 100644
index 00000000000..4bb0f7dd8e6
--- /dev/null
+++ b/policyengine_us/variables/gov/states/wa/pfml/wa_pfml_eligible.py
@@ -0,0 +1,25 @@
+from policyengine_us.model_api import *
+
+
+class wa_pfml_eligible(Variable):
+    value_type = bool
+    entity = Person
+    label = "Washington PFML eligible"
+    documentation = (
+        "Eligibility for Washington Paid Family and Medical Leave "
+        "benefits. Requires working at least the qualifying hours "
+        "threshold in the qualifying period per RCW 50A.15.010. "
+        "If no qualifying-period hours override is provided, annual hours "
+        "worked are approximated as weekly hours worked multiplied by the "
+        "number of weeks in a year."
+    )
+    definition_period = YEAR
+    defined_for = StateCode.WA
+    reference = "https://app.leg.wa.gov/rcw/default.aspx?cite=50A.15.010"
+
+    def formula(person, period, parameters):
+        p = parameters(period).gov.states.wa.pfml
+        hours_override = person("wa_pfml_qualifying_period_hours_worked", period)
+        annual_hours = person("weekly_hours_worked", period) * WEEKS_IN_YEAR
+        qualifying_hours = where(hours_override >= 0, hours_override, annual_hours)
+        return qualifying_hours >= p.hours_threshold
diff --git a/policyengine_us/variables/gov/states/wa/pfml/wa_pfml_leave_type.py b/policyengine_us/variables/gov/states/wa/pfml/wa_pfml_leave_type.py
new file mode 100644
index 00000000000..cee4f9da9e3
--- /dev/null
+++ b/policyengine_us/variables/gov/states/wa/pfml/wa_pfml_leave_type.py
@@ -0,0 +1,21 @@
+from policyengine_us.model_api import *
+
+
+class WAPFMLLeaveType(Enum):
+    FAMILY = "Family"
+    MEDICAL = "Medical"
+    COMBINED = "Combined"
+    MEDICAL_WITH_PREGNANCY_INCAPACITY = "Medical with pregnancy incapacity"
+    COMBINED_WITH_PREGNANCY_INCAPACITY = "Combined with pregnancy incapacity"
+    NONE = "None"
+
+
+class wa_pfml_leave_type(Variable):
+    value_type = Enum
+    entity = Person
+    label = "Washington PFML selected leave type"
+    definition_period = YEAR
+    possible_values = WAPFMLLeaveType
+    default_value = WAPFMLLeaveType.NONE
+    defined_for = StateCode.WA
+    reference = "https://app.leg.wa.gov/rcw/default.aspx?cite=50A.15.020"
diff --git a/policyengine_us/variables/gov/states/wa/pfml/wa_pfml_max_leave_weeks.py b/policyengine_us/variables/gov/states/wa/pfml/wa_pfml_max_leave_weeks.py
new file mode 100644
index 00000000000..d6f1ee934a3
--- /dev/null
+++ b/policyengine_us/variables/gov/states/wa/pfml/wa_pfml_max_leave_weeks.py
@@ -0,0 +1,40 @@
+from policyengine_us.model_api import *
+
+
+class wa_pfml_max_leave_weeks(Variable):
+    value_type = float
+    entity = Person
+    label = "Washington PFML maximum leave weeks"
+    documentation = (
+        "Maximum Washington Paid Family and Medical Leave duration in weeks "
+        "for the selected leave type."
+    )
+    unit = "week"
+    definition_period = YEAR
+    defined_for = "wa_pfml_eligible"
+    reference = (
+        "https://app.leg.wa.gov/rcw/default.aspx?cite=50A.15.020",
+        "https://app.leg.wa.gov/rcw/default.aspx?cite=50A.15.010",
+    )
+
+    def formula(person, period, parameters):
+        p = parameters(period).gov.states.wa.pfml
+        leave_type = person("wa_pfml_leave_type", period)
+        leave_type_values = leave_type.possible_values
+        return select(
+            [
+                leave_type == leave_type_values.FAMILY,
+                leave_type == leave_type_values.MEDICAL,
+                leave_type == leave_type_values.COMBINED,
+                leave_type == leave_type_values.MEDICAL_WITH_PREGNANCY_INCAPACITY,
+                leave_type == leave_type_values.COMBINED_WITH_PREGNANCY_INCAPACITY,
+            ],
+            [
+                p.duration.family_leave_weeks,
+                p.duration.medical_leave_weeks,
+                p.duration.combined_max_weeks,
+                p.duration.medical_leave_weeks_with_pregnancy_incapacity,
+                p.duration.combined_max_weeks_with_pregnancy_incapacity,
+            ],
+            default=0,
+        )
diff --git a/policyengine_us/variables/gov/states/wa/pfml/wa_pfml_qualifying_period_hours_worked.py b/policyengine_us/variables/gov/states/wa/pfml/wa_pfml_qualifying_period_hours_worked.py
new file mode 100644
index 00000000000..e56ea68cca1
--- /dev/null
+++ b/policyengine_us/variables/gov/states/wa/pfml/wa_pfml_qualifying_period_hours_worked.py
@@ -0,0 +1,17 @@
+from policyengine_us.model_api import *
+
+
+class wa_pfml_qualifying_period_hours_worked(Variable):
+    value_type = float
+    entity = Person
+    label = "Washington PFML qualifying-period hours worked override"
+    documentation = (
+        "Optional override for hours worked in the Washington PFML "
+        "qualifying period. Set to a non-negative number of hours to replace "
+        "the annualized weekly-hours proxy used for eligibility."
+    )
+    unit = "hour"
+    definition_period = YEAR
+    defined_for = StateCode.WA
+    default_value = -1
+    reference = "https://app.leg.wa.gov/rcw/default.aspx?cite=50A.15.010"
diff --git a/policyengine_us/variables/gov/states/wa/pfml/wa_pfml_weekly_benefit_amount.py b/policyengine_us/variables/gov/states/wa/pfml/wa_pfml_weekly_benefit_amount.py
new file mode 100644
index 00000000000..0d0f77be48b
--- /dev/null
+++ b/policyengine_us/variables/gov/states/wa/pfml/wa_pfml_weekly_benefit_amount.py
@@ -0,0 +1,39 @@
+from policyengine_us.model_api import *
+
+
+class wa_pfml_weekly_benefit_amount(Variable):
+    value_type = float
+    entity = Person
+    label = "Washington PFML weekly benefit amount"
+    documentation = (
+        "Weekly benefit amount under Washington Paid Family and Medical "
+        "Leave. Applies the two-tier replacement formula in "
+        "RCW 50A.15.020(5), rounds down to the next lower dollar, and clips "
+        "the result to the statutory minimum and maximum weekly benefit "
+        "amounts. Despite the YEAR definition period, this variable "
+        "represents a weekly dollar amount."
+    )
+    unit = USD
+    definition_period = YEAR
+    defined_for = StateCode.WA
+    reference = (
+        "https://app.leg.wa.gov/rcw/default.aspx?cite=50A.15.020",
+        "https://paidleave.wa.gov/app/uploads/2025/12/Paycheck-insert-2026-1.pdf",
+    )
+
+    def formula(person, period, parameters):
+        p = parameters(period).gov.states.wa.pfml
+        aww = person("wa_pfml_average_weekly_wage", period)
+        lower_threshold = p.lower_threshold_fraction * p.state_average_weekly_wage
+        lower_benefit = p.lower_benefit_rate * min_(aww, lower_threshold)
+        upper_benefit = p.upper_benefit_rate * max_(aww - lower_threshold, 0)
+        raw_benefit = np.floor(lower_benefit + upper_benefit)
+        # Per RCW 50A.15.020(6)(b): minimum is $100, or AWW if AWW < $100.
+        # Using min_(min_amount, aww) as the floor naturally handles zero AWW
+        # (no employment → floor=0 → benefit=0) and low AWW (floor=AWW).
+        effective_min = min_(p.min_weekly_benefit_amount, aww)
+        return clip(
+            raw_benefit,
+            effective_min,
+            p.max_weekly_benefit_amount,
+        )