diff --git a/changelog.d/wa-millionaires-tax.added.md b/changelog.d/wa-millionaires-tax.added.md
new file mode 100644
index 00000000000..461bbabbff9
--- /dev/null
+++ b/changelog.d/wa-millionaires-tax.added.md
@@ -0,0 +1 @@
+Add Washington millionaires tax (9.9% on income above $1M) and WFTC age expansion (18+) per ESSB 6346. Removes contributed reform since bill is now law.
diff --git a/policyengine_us/parameters/gov/contrib/states/wa/sb6346/charitable_deduction/cap/individual.yaml b/policyengine_us/parameters/gov/contrib/states/wa/sb6346/charitable_deduction/cap/individual.yaml
deleted file mode 100644
index d6f8d582335..00000000000
--- a/policyengine_us/parameters/gov/contrib/states/wa/sb6346/charitable_deduction/cap/individual.yaml
+++ /dev/null
@@ -1,12 +0,0 @@
-description: Washington limits the charitable contribution deduction to this amount per individual under the SSB 6346 reform.
-
-values:
-  2028-01-01: 100_000
-
-metadata:
-  unit: currency-USD
-  period: year
-  label: Washington SSB 6346 individual charitable deduction cap
-  reference:
-    - title: SSB 6346, Sec. 307 - Charitable Contributions
-      href: https://lawfilesext.leg.wa.gov/biennium/2025-26/Pdf/Bills/Senate%20Bills/6346-S.pdf#page=10
diff --git a/policyengine_us/parameters/gov/contrib/states/wa/sb6346/charitable_deduction/cap/joint.yaml b/policyengine_us/parameters/gov/contrib/states/wa/sb6346/charitable_deduction/cap/joint.yaml
deleted file mode 100644
index 298b9b479c3..00000000000
--- a/policyengine_us/parameters/gov/contrib/states/wa/sb6346/charitable_deduction/cap/joint.yaml
+++ /dev/null
@@ -1,12 +0,0 @@
-description: Washington limits the combined charitable contribution deduction for married couples to this amount under the SSB 6346 reform.
-
-values:
-  2028-01-01: 100_000
-
-metadata:
-  unit: currency-USD
-  period: year
-  label: Washington SSB 6346 joint charitable deduction cap
-  reference:
-    - title: SSB 6346, Sec. 307 - Charitable Contributions
-      href: https://lawfilesext.leg.wa.gov/biennium/2025-26/Pdf/Bills/Senate%20Bills/6346-S.pdf#page=10
diff --git a/policyengine_us/parameters/gov/contrib/states/wa/sb6346/in_effect.yaml b/policyengine_us/parameters/gov/contrib/states/wa/sb6346/in_effect.yaml
deleted file mode 100644
index c4270ebe8db..00000000000
--- a/policyengine_us/parameters/gov/contrib/states/wa/sb6346/in_effect.yaml
+++ /dev/null
@@ -1,12 +0,0 @@
-description: Washington uses this indicator to determine whether the SSB 6346 income tax reform is in effect.
-
-values:
-  2024-01-01: false
-
-metadata:
-  unit: bool
-  period: year
-  label: Washington SSB 6346 income tax reform in effect
-  reference:
-    - title: SSB 6346, 69th Legislature, 2025-2026
-      href: https://lawfilesext.leg.wa.gov/biennium/2025-26/Pdf/Bills/Senate%20Bills/6346-S.pdf#page=1
diff --git a/policyengine_us/parameters/gov/contrib/states/wa/sb6346/rate.yaml b/policyengine_us/parameters/gov/contrib/states/wa/sb6346/rate.yaml
deleted file mode 100644
index a1166deeb0a..00000000000
--- a/policyengine_us/parameters/gov/contrib/states/wa/sb6346/rate.yaml
+++ /dev/null
@@ -1,12 +0,0 @@
-description: Washington sets the income tax rate to this share under the SSB 6346 reform.
-
-values:
-  2028-01-01: 0.099
-
-metadata:
-  unit: /1
-  period: year
-  label: Washington SSB 6346 income tax rate
-  reference:
-    - title: SSB 6346, Sec. 201(1) - Tax Imposed
-      href: https://lawfilesext.leg.wa.gov/biennium/2025-26/Pdf/Bills/Senate%20Bills/6346-S.pdf#page=6
diff --git a/policyengine_us/parameters/gov/contrib/states/wa/sb6346/standard_deduction/amount.yaml b/policyengine_us/parameters/gov/contrib/states/wa/sb6346/standard_deduction/amount.yaml
deleted file mode 100644
index 4d0e7de520b..00000000000
--- a/policyengine_us/parameters/gov/contrib/states/wa/sb6346/standard_deduction/amount.yaml
+++ /dev/null
@@ -1,21 +0,0 @@
-description: Washington provides this amount as the standard deduction under the SSB 6346 reform.
-
-values:
-  2028-01-01: 1_000_000
-
-metadata:
-  unit: currency-USD
-  period: year
-  label: Washington SSB 6346 standard deduction
-  uprating: gov.bls.cpi.cpi_u
-  # Sec. 312 specifies Seattle-area CPI-U for indexing starting Oct 2029
-  # (for tax year 2030). Using national CPI-U as a proxy until we add
-  # Seattle-area CPI data. Fixed at $1M for 2028-2029.
-  rounding:
-    type: nearest
-    interval: 1_000
-  reference:
-    - title: SSB 6346, Sec. 310 - One million dollar standard deduction
-      href: https://lawfilesext.leg.wa.gov/biennium/2025-26/Pdf/Bills/Senate%20Bills/6346-S.pdf#page=10
-    - title: SSB 6346, Sec. 312(1) - Index for inflation
-      href: https://lawfilesext.leg.wa.gov/biennium/2025-26/Pdf/Bills/Senate%20Bills/6346-S.pdf#page=11
diff --git a/policyengine_us/parameters/gov/contrib/states/wa/sb6346/wftc/in_effect.yaml b/policyengine_us/parameters/gov/contrib/states/wa/sb6346/wftc/in_effect.yaml
deleted file mode 100644
index 91bd69c832d..00000000000
--- a/policyengine_us/parameters/gov/contrib/states/wa/sb6346/wftc/in_effect.yaml
+++ /dev/null
@@ -1,15 +0,0 @@
-description: Washington uses this indicator to determine whether the SSB 6346 Working Families Tax Credit age expansion is in effect.
-
-values:
-  2024-01-01: false
-  2029-01-01: true
-
-metadata:
-  unit: bool
-  period: year
-  label: Washington SSB 6346 WFTC age expansion in effect
-  reference:
-    - title: SSB 6346, Sec. 901(2)(a)(ii)(C)
-      href: https://lawfilesext.leg.wa.gov/biennium/2025-26/Pdf/Bills/Senate%20Bills/6346-S.pdf#page=53
-    - title: SSB 6346, Sec. 1005(1)
-      href: https://lawfilesext.leg.wa.gov/biennium/2025-26/Pdf/Bills/Senate%20Bills/6346-S.pdf#page=63
diff --git a/policyengine_us/parameters/gov/contrib/states/wa/sb6346/wftc/min_age.yaml b/policyengine_us/parameters/gov/contrib/states/wa/sb6346/wftc/min_age.yaml
deleted file mode 100644
index 1b7c8624d98..00000000000
--- a/policyengine_us/parameters/gov/contrib/states/wa/sb6346/wftc/min_age.yaml
+++ /dev/null
@@ -1,16 +0,0 @@
-description: Washington sets this age threshold for expanded Working Families Tax Credit eligibility under the SSB 6346 reform.
-
-values:
-  2029-01-01: 18
-
-# PolicyEngine does not model the WFTC's claim-year timing separately from the
-# simulated tax year, so the later effective date in Sec. 1005(1) is enforced
-# through the companion wftc/in_effect parameter rather than by backdating this
-# threshold before 2029.
-metadata:
-  unit: year
-  period: year
-  label: Washington SSB 6346 WFTC minimum age threshold
-  reference:
-    - title: SSB 6346, Sec. 901(2)(a)(ii)(C)
-      href: https://lawfilesext.leg.wa.gov/biennium/2025-26/Pdf/Bills/Senate%20Bills/6346-S.pdf#page=53
diff --git a/policyengine_us/parameters/gov/states/wa/tax/income/credits/working_families_tax_credit/age_expansion/in_effect.yaml b/policyengine_us/parameters/gov/states/wa/tax/income/credits/working_families_tax_credit/age_expansion/in_effect.yaml
new file mode 100644
index 00000000000..a4062b81c32
--- /dev/null
+++ b/policyengine_us/parameters/gov/states/wa/tax/income/credits/working_families_tax_credit/age_expansion/in_effect.yaml
@@ -0,0 +1,13 @@
+description: Washington uses this indicator to determine whether the Working Families Tax Credit age expansion applies.
+values:
+  2000-01-01: false
+  2029-01-01: true
+metadata:
+  unit: bool
+  period: year
+  label: Washington WFTC age expansion in effect
+  reference:
+    - title: ESSB 6346, Sec. 901 - Working Families Tax Credit expansion
+      href: https://lawfilesext.leg.wa.gov/biennium/2025-26/Pdf/Bills/Senate%20Passed%20Legislature/6346-S.PL.pdf#page=61
+    - title: ESSB 6346, Sec. 1205(1) - Effective date
+      href: https://lawfilesext.leg.wa.gov/biennium/2025-26/Pdf/Bills/Senate%20Passed%20Legislature/6346-S.PL.pdf#page=110
diff --git a/policyengine_us/parameters/gov/states/wa/tax/income/credits/working_families_tax_credit/age_expansion/min_age.yaml b/policyengine_us/parameters/gov/states/wa/tax/income/credits/working_families_tax_credit/age_expansion/min_age.yaml
new file mode 100644
index 00000000000..e35301f1a39
--- /dev/null
+++ b/policyengine_us/parameters/gov/states/wa/tax/income/credits/working_families_tax_credit/age_expansion/min_age.yaml
@@ -0,0 +1,11 @@
+description: Washington sets this age as the minimum for eligibility under the Working Families Tax Credit age expansion.
+values:
+  2000-01-01: 0
+  2029-01-01: 18
+metadata:
+  unit: year
+  period: year
+  label: Washington WFTC minimum age for expansion
+  reference:
+    - title: ESSB 6346, Sec. 901(2)(a)(ii)(D) - Age requirement
+      href: https://lawfilesext.leg.wa.gov/biennium/2025-26/Pdf/Bills/Senate%20Passed%20Legislature/6346-S.PL.pdf#page=61
diff --git a/policyengine_us/parameters/gov/states/wa/tax/income/millionaires_tax/deductions/charitable/cap.yaml b/policyengine_us/parameters/gov/states/wa/tax/income/millionaires_tax/deductions/charitable/cap.yaml
new file mode 100644
index 00000000000..cb257e8d977
--- /dev/null
+++ b/policyengine_us/parameters/gov/states/wa/tax/income/millionaires_tax/deductions/charitable/cap.yaml
@@ -0,0 +1,10 @@
+description: Washington limits charitable deductions to this amount under the millionaires tax.
+values:
+  2028-01-01: 100_000
+metadata:
+  unit: currency-USD
+  period: year
+  label: Washington millionaires tax charitable deduction cap
+  reference:
+    - title: ESSB 6346, Sec. 309(1) - Charitable contributions
+      href: https://lawfilesext.leg.wa.gov/biennium/2025-26/Pdf/Bills/Senate%20Passed%20Legislature/6346-S.PL.pdf#page=14
diff --git a/policyengine_us/parameters/gov/states/wa/tax/income/millionaires_tax/deductions/standard.yaml b/policyengine_us/parameters/gov/states/wa/tax/income/millionaires_tax/deductions/standard.yaml
new file mode 100644
index 00000000000..62b67830155
--- /dev/null
+++ b/policyengine_us/parameters/gov/states/wa/tax/income/millionaires_tax/deductions/standard.yaml
@@ -0,0 +1,19 @@
+description: Washington deducts this amount as the standard deduction under the millionaires tax.
+values:
+  2028-01-01: 1_000_000
+metadata:
+  unit: currency-USD
+  period: year
+  label: Washington millionaires tax standard deduction
+  uprating: gov.bls.cpi.cpi_u
+  # Sec. 316 specifies Seattle-area CPI-U for indexing starting Oct 2029
+  # (for tax year 2030). Using national CPI-U as a proxy until we add
+  # Seattle-area CPI data. Fixed at $1M for 2028-2029.
+  rounding:
+    type: nearest
+    interval: 1_000
+  reference:
+    - title: ESSB 6346, Sec. 314 - One million dollar standard deduction
+      href: https://lawfilesext.leg.wa.gov/biennium/2025-26/Pdf/Bills/Senate%20Passed%20Legislature/6346-S.PL.pdf#page=15
+    - title: ESSB 6346, Sec. 316(1) - Index for inflation
+      href: https://lawfilesext.leg.wa.gov/biennium/2025-26/Pdf/Bills/Senate%20Passed%20Legislature/6346-S.PL.pdf#page=15
diff --git a/policyengine_us/parameters/gov/states/wa/tax/income/millionaires_tax/in_effect.yaml b/policyengine_us/parameters/gov/states/wa/tax/income/millionaires_tax/in_effect.yaml
new file mode 100644
index 00000000000..61d6caa895e
--- /dev/null
+++ b/policyengine_us/parameters/gov/states/wa/tax/income/millionaires_tax/in_effect.yaml
@@ -0,0 +1,11 @@
+description: Washington applies the millionaires tax if this is true.
+values:
+  2000-01-01: false
+  2028-01-01: true
+metadata:
+  unit: bool
+  period: year
+  label: Washington millionaires tax in effect
+  reference:
+    - title: ESSB 6346, Sec. 201(1) - Tax Imposed
+      href: https://lawfilesext.leg.wa.gov/biennium/2025-26/Pdf/Bills/Senate%20Passed%20Legislature/6346-S.PL.pdf#page=8
diff --git a/policyengine_us/parameters/gov/states/wa/tax/income/millionaires_tax/rate.yaml b/policyengine_us/parameters/gov/states/wa/tax/income/millionaires_tax/rate.yaml
new file mode 100644
index 00000000000..454f7aaeaef
--- /dev/null
+++ b/policyengine_us/parameters/gov/states/wa/tax/income/millionaires_tax/rate.yaml
@@ -0,0 +1,10 @@
+description: Washington taxes income at this rate under the millionaires tax.
+values:
+  2028-01-01: 0.099
+metadata:
+  unit: /1
+  period: year
+  label: Washington millionaires tax rate
+  reference:
+    - title: ESSB 6346, Sec. 201(1) - Tax Imposed
+      href: https://lawfilesext.leg.wa.gov/biennium/2025-26/Pdf/Bills/Senate%20Passed%20Legislature/6346-S.PL.pdf#page=8
diff --git a/policyengine_us/reforms/reforms.py b/policyengine_us/reforms/reforms.py
index f774002d35c..46f15a2d67b 100644
--- a/policyengine_us/reforms/reforms.py
+++ b/policyengine_us/reforms/reforms.py
@@ -184,9 +184,6 @@
 from .congress.watca import (
     create_watca_reform,
 )
-from .states.wa.sb6346.sb6346 import (
-    create_wa_sb6346_reform,
-)
 
 
 from .states.ga.sb520 import (
@@ -411,7 +408,6 @@ def create_structural_reforms_from_parameters(parameters, period):
     nc_eitc = create_nc_eitc_reform(parameters, period)
     mi_ctc = create_mi_ctc_reform(parameters, period)
     watca = create_watca_reform(parameters, period)
-    wa_sb6346 = create_wa_sb6346_reform(parameters, period)
     al_eitc = create_al_eitc_reform(parameters, period)
     ar_eitc = create_ar_eitc_reform(parameters, period)
     az_eitc = create_az_eitc_reform(parameters, period)
@@ -516,7 +512,6 @@ def create_structural_reforms_from_parameters(parameters, period):
         nc_eitc,
         mi_ctc,
         watca,
-        wa_sb6346,
         al_eitc,
         ar_eitc,
         az_eitc,
diff --git a/policyengine_us/reforms/states/wa/sb6346/__init__.py b/policyengine_us/reforms/states/wa/sb6346/__init__.py
deleted file mode 100644
index 9fca7b7fed4..00000000000
--- a/policyengine_us/reforms/states/wa/sb6346/__init__.py
+++ /dev/null
@@ -1 +0,0 @@
-from .sb6346 import create_wa_sb6346_reform, wa_sb6346
diff --git a/policyengine_us/reforms/states/wa/sb6346/sb6346.py b/policyengine_us/reforms/states/wa/sb6346/sb6346.py
deleted file mode 100644
index 7f3596eb131..00000000000
--- a/policyengine_us/reforms/states/wa/sb6346/sb6346.py
+++ /dev/null
@@ -1,194 +0,0 @@
-from policyengine_us.model_api import *
-from policyengine_core.periods import period as period_
-
-
-def create_wa_sb6346() -> Reform:
-    """
-    WA SSB 6346 - 9.9% income tax on high earners.
-
-    Imposes a 9.9% tax on Washington taxable income (federal AGI minus
-    a $1M standard deduction and capped charitable deduction).
-
-    Reference: https://lawfilesext.leg.wa.gov/biennium/2025-26/Pdf/Bills/Senate%20Bills/6346-S.pdf
-    """
-
-    class wa_income_tax_base_income(Variable):
-        value_type = float
-        entity = TaxUnit
-        label = "Washington base income under SSB 6346"
-        unit = USD
-        definition_period = YEAR
-        reference = "https://lawfilesext.leg.wa.gov/biennium/2025-26/Pdf/Bills/Senate%20Bills/6346-S.pdf#page=5"
-        defined_for = StateCode.WA
-        adds = ["adjusted_gross_income"]
-
-    class wa_income_tax_charitable_deduction(Variable):
-        value_type = float
-        entity = TaxUnit
-        label = "Washington income tax charitable deduction under SSB 6346"
-        unit = USD
-        definition_period = YEAR
-        reference = "https://lawfilesext.leg.wa.gov/biennium/2025-26/Pdf/Bills/Senate%20Bills/6346-S.pdf#page=10"
-        defined_for = StateCode.WA
-
-        def formula(tax_unit, period, parameters):
-            p = parameters(period).gov.contrib.states.wa.sb6346.charitable_deduction.cap
-            filing_status = tax_unit("filing_status", period)
-            charitable = add(
-                tax_unit,
-                period,
-                ["charitable_cash_donations", "charitable_non_cash_donations"],
-            )
-            is_joint = filing_status == filing_status.possible_values.JOINT
-            cap = where(is_joint, p.joint, p.individual)
-            return min_(charitable, cap)
-
-    class wa_income_tax_standard_deduction(Variable):
-        value_type = float
-        entity = TaxUnit
-        label = "Washington income tax standard deduction under SSB 6346"
-        unit = USD
-        definition_period = YEAR
-        reference = "https://lawfilesext.leg.wa.gov/biennium/2025-26/Pdf/Bills/Senate%20Bills/6346-S.pdf#page=10"
-        defined_for = StateCode.WA
-        adds = ["gov.contrib.states.wa.sb6346.standard_deduction.amount"]
-
-    class wa_income_tax_taxable_income(Variable):
-        value_type = float
-        entity = TaxUnit
-        label = "Washington taxable income under SSB 6346"
-        unit = USD
-        definition_period = YEAR
-        reference = (
-            "https://lawfilesext.leg.wa.gov/biennium/2025-26/Pdf/Bills/Senate%20Bills/6346-S.pdf#page=10",
-            "https://lawfilesext.leg.wa.gov/biennium/2025-26/Pdf/Bills/Senate%20Bills/6346-S.pdf#page=11",
-        )
-        defined_for = StateCode.WA
-
-        def formula(tax_unit, period, parameters):
-            in_effect = parameters(period).gov.contrib.states.wa.sb6346.in_effect
-            base_income = tax_unit("wa_income_tax_base_income", period)
-            charitable_deduction = tax_unit(
-                "wa_income_tax_charitable_deduction", period
-            )
-            standard_deduction = tax_unit("wa_income_tax_standard_deduction", period)
-            return where(
-                in_effect,
-                max_(base_income - charitable_deduction - standard_deduction, 0),
-                0,
-            )
-
-    class wa_income_tax_before_refundable_credits(Variable):
-        value_type = float
-        entity = TaxUnit
-        label = "Washington income tax before refundable credits"
-        unit = USD
-        definition_period = YEAR
-        reference = "https://lawfilesext.leg.wa.gov/biennium/2025-26/Pdf/Bills/Senate%20Bills/6346-S.pdf#page=6"
-        defined_for = StateCode.WA
-
-        def formula(tax_unit, period, parameters):
-            p = parameters(period).gov.contrib.states.wa.sb6346
-            in_effect = p.in_effect
-            taxable_income = tax_unit("wa_income_tax_taxable_income", period)
-            sb6346_tax = taxable_income * p.rate
-            capital_gains_tax = tax_unit("wa_capital_gains_tax", period)
-            return where(in_effect, sb6346_tax + capital_gains_tax, capital_gains_tax)
-
-    class wa_income_tax(Variable):
-        value_type = float
-        entity = TaxUnit
-        label = "Washington income tax"
-        unit = USD
-        definition_period = YEAR
-        reference = "https://lawfilesext.leg.wa.gov/biennium/2025-26/Pdf/Bills/Senate%20Bills/6346-S.pdf#page=6"
-        defined_for = StateCode.WA
-        adds = ["wa_income_tax_before_refundable_credits"]
-        subtracts = ["wa_refundable_credits"]
-
-    class wa_working_families_tax_credit(Variable):
-        value_type = float
-        entity = TaxUnit
-        label = "Washington Working Families Tax Credit"
-        unit = USD
-        definition_period = YEAR
-        reference = (
-            "https://app.leg.wa.gov/RCW/default.aspx?cite=82.08.0206",
-            "https://lawfilesext.leg.wa.gov/biennium/2025-26/Pdf/Bills/Senate%20Bills/6346-S.pdf#page=53",
-        )
-        defined_for = StateCode.WA
-
-        def formula(tax_unit, period, parameters):
-            eitc = tax_unit("eitc", period)
-            eitc_eligible = eitc > 0
-            # SSB 6346 Sec. 901(2)(a)(ii)(C): individuals who do not meet
-            # the EITC age requirement but are at least age 18.
-            reform_in_effect = parameters(period).gov.contrib.states.wa.sb6346.in_effect
-            sb6346_p = parameters(period).gov.contrib.states.wa.sb6346.wftc
-            expansion_in_effect = reform_in_effect & sb6346_p.in_effect
-            age_head = tax_unit("age_head", period)
-            age_spouse = tax_unit("age_spouse", period)
-            filer_at_least_min_age = expansion_in_effect & (
-                (age_head >= sb6346_p.min_age) | (age_spouse >= sb6346_p.min_age)
-            )
-            earned_income = tax_unit("filer_adjusted_earnings", period)
-            has_earned_income = earned_income > 0
-            eligible = eitc_eligible | (filer_at_least_min_age & has_earned_income)
-            p = parameters(
-                period
-            ).gov.states.wa.tax.income.credits.working_families_tax_credit
-            eitc_child_count = tax_unit("eitc_child_count", period)
-            max_amount = p.amount.calc(eitc_child_count)
-            eitc_agi_limit = tax_unit("eitc_agi_limit", period)
-            phase_out_start_reduction = p.phase_out.start_below_eitc.calc(
-                eitc_child_count
-            )
-            phase_out_start = eitc_agi_limit - phase_out_start_reduction
-            phase_out_rate = (max_amount - p.min_amount) / phase_out_start_reduction
-            excess = max_(0, earned_income - phase_out_start)
-            reduction = max_(0, excess * phase_out_rate)
-            phased_out_amount = max_amount - reduction
-            amount_if_eligible = where(
-                phased_out_amount > 0,
-                max_(p.min_amount, phased_out_amount),
-                0,
-            )
-            return amount_if_eligible * eligible
-
-    class reform(Reform):
-        def apply(self):
-            self.update_variable(wa_income_tax_base_income)
-            self.update_variable(wa_income_tax_charitable_deduction)
-            self.update_variable(wa_income_tax_standard_deduction)
-            self.update_variable(wa_income_tax_taxable_income)
-            self.update_variable(wa_income_tax_before_refundable_credits)
-            self.update_variable(wa_income_tax)
-            self.update_variable(wa_working_families_tax_credit)
-
-    return reform
-
-
-def create_wa_sb6346_reform(parameters, period, bypass=False):
-    if bypass:
-        return create_wa_sb6346()
-
-    p = parameters.gov.contrib.states.wa.sb6346
-
-    reform_active = False
-    current_period = period_(period)
-
-    # Match the standard five-year structural reform lookahead used across
-    # the repo so future-year simulations can pick up contributed reforms.
-    for _ in range(5):
-        if p(current_period).in_effect:
-            reform_active = True
-            break
-        current_period = current_period.offset(1, "year")
-
-    if reform_active:
-        return create_wa_sb6346()
-    else:
-        return None
-
-
-wa_sb6346 = create_wa_sb6346_reform(None, None, bypass=True)
diff --git a/policyengine_us/tests/policy/baseline/gov/states/wa/tax/income/credits/wa_working_families_tax_credit.yaml b/policyengine_us/tests/policy/baseline/gov/states/wa/tax/income/credits/wa_working_families_tax_credit.yaml
index 422d42cf1ec..e3b86a448e9 100644
--- a/policyengine_us/tests/policy/baseline/gov/states/wa/tax/income/credits/wa_working_families_tax_credit.yaml
+++ b/policyengine_us/tests/policy/baseline/gov/states/wa/tax/income/credits/wa_working_families_tax_credit.yaml
@@ -1,4 +1,7 @@
-- name: Ineligible without EITC.
+# Washington Working Families Tax Credit tests
+# RCW 82.08.0206 and ESSB 6346 Sec. 901 (age expansion)
+
+- name: Case 1, ineligible without EITC.
   period: 2022
   absolute_error_margin: 0
   input:
@@ -6,7 +9,7 @@
   output:
     wa_working_families_tax_credit: 0
 
-- name: Single eligible person with no income will get the maximum credit.
+- name: Case 2, single eligible person with no income gets maximum credit.
   period: 2022
   absolute_error_margin: 0
   input:
@@ -17,7 +20,7 @@
   output:
     wa_working_families_tax_credit: 300
 
-- name: Family with income over the limit doesn't receive it.
+- name: Case 3, family with income over the limit receives no credit.
   period: 2022
   absolute_error_margin: 0
   input:
@@ -28,7 +31,7 @@
   output:
     wa_working_families_tax_credit: 0
 
-- name: At EITC AGI limit, credit phases to $50 minimum per RCW 82.08.0206(3)(f).
+- name: Case 4, at EITC AGI limit credit phases to $50 minimum.
   period: 2024
   absolute_error_margin: 0.01
   input:
@@ -38,9 +41,10 @@
     eitc_agi_limit: 50_000
     filer_adjusted_earnings: 50_000
   output:
+    # Per RCW 82.08.0206(3)(f), minimum credit is $50
     wa_working_families_tax_credit: 50
 
-- name: Mid-phaseout gives correctly reduced credit.
+- name: Case 5, mid-phaseout gives correctly reduced credit.
   period: 2024
   absolute_error_margin: 0.01
   input:
@@ -52,7 +56,7 @@
   output:
     wa_working_families_tax_credit: 345
 
-- name: Joint filer with 1 child and moderate income receives credit.
+- name: Case 6, joint filer with 1 child and moderate income receives credit.
   period: 2024
   absolute_error_margin: 50
   input:
@@ -81,3 +85,68 @@
         state_code: WA
   output:
     wa_working_families_tax_credit: 640
+
+# ESSB 6346 Sec. 901 - WFTC Age Expansion tests (effective 2029)
+
+- name: Case 7, age 18+ without EITC gets WFTC under 2029 age expansion.
+  period: 2029
+  absolute_error_margin: 1
+  input:
+    state_code: WA
+    age_head: 20
+    eitc: 0
+    filer_adjusted_earnings: 10_000
+    eitc_child_count: 0
+  output:
+    # Eligible via age expansion: age 18+, has earned income
+    # Amount is inflation-adjusted from $300 (2022) to ~$367 (2029)
+    wa_working_families_tax_credit: 367
+
+- name: Case 8, age 17 without EITC gets no WFTC in 2029.
+  period: 2029
+  input:
+    state_code: WA
+    age_head: 17
+    eitc: 0
+    filer_adjusted_earnings: 10_000
+    eitc_child_count: 0
+  output:
+    # Not EITC eligible and under age 18 minimum
+    wa_working_families_tax_credit: 0
+
+- name: Case 9, age 18+ without earned income gets no WFTC in 2029.
+  period: 2029
+  input:
+    state_code: WA
+    age_head: 25
+    eitc: 0
+    filer_adjusted_earnings: 0
+    eitc_child_count: 0
+  output:
+    # Age expansion requires earned income
+    wa_working_families_tax_credit: 0
+
+- name: Case 10, WFTC age expansion not in effect before 2029.
+  period: 2028
+  input:
+    state_code: WA
+    age_head: 20
+    eitc: 0
+    filer_adjusted_earnings: 10_000
+    eitc_child_count: 0
+  output:
+    # Age expansion starts 2029, no EITC eligibility
+    wa_working_families_tax_credit: 0
+
+- name: Case 11, traditional EITC-eligible filer still works in 2029.
+  period: 2029
+  absolute_error_margin: 1
+  input:
+    state_code: WA
+    eitc: 1
+    filer_adjusted_earnings: 0
+    eitc_child_count: 0
+  output:
+    # Standard EITC pathway still works
+    # Amount is inflation-adjusted from $300 (2022) to ~$367 (2029)
+    wa_working_families_tax_credit: 367
diff --git a/policyengine_us/tests/policy/baseline/gov/states/wa/tax/income/millionaires_tax/wa_millionaires_tax.yaml b/policyengine_us/tests/policy/baseline/gov/states/wa/tax/income/millionaires_tax/wa_millionaires_tax.yaml
new file mode 100644
index 00000000000..d835eaa33ad
--- /dev/null
+++ b/policyengine_us/tests/policy/baseline/gov/states/wa/tax/income/millionaires_tax/wa_millionaires_tax.yaml
@@ -0,0 +1,163 @@
+# Washington Millionaires Tax tests
+# ESSB 6346 imposes a 9.9% tax on Washington taxable income above $1,000,000
+# Effective January 1, 2028
+
+- name: Case 1, single filer with $2M income.
+  period: 2028
+  absolute_error_margin: 1
+  input:
+    state_code: WA
+    adjusted_gross_income: 2_000_000
+  output:
+    # Taxable income = $2M - $1M standard deduction = $1M
+    # Tax = $1M * 9.9% = $99,000
+    wa_millionaires_tax: 99_000
+
+- name: Case 2, single filer with $1.5M income.
+  period: 2028
+  absolute_error_margin: 1
+  input:
+    state_code: WA
+    adjusted_gross_income: 1_500_000
+  output:
+    # Taxable income = $1.5M - $1M standard deduction = $500K
+    # Tax = $500K * 9.9% = $49,500
+    wa_millionaires_tax: 49_500
+
+- name: Case 3, single filer below $1M threshold.
+  period: 2028
+  absolute_error_margin: 1
+  input:
+    state_code: WA
+    adjusted_gross_income: 900_000
+  output:
+    # Income below $1M standard deduction, no tax owed
+    wa_millionaires_tax: 0
+
+- name: Case 4, single filer exactly at $1M threshold.
+  period: 2028
+  absolute_error_margin: 1
+  input:
+    state_code: WA
+    adjusted_gross_income: 1_000_000
+  output:
+    # Taxable income = $1M - $1M = $0
+    wa_millionaires_tax: 0
+
+- name: Case 5, single filer just above $1M threshold.
+  period: 2028
+  absolute_error_margin: 1
+  input:
+    state_code: WA
+    adjusted_gross_income: 1_001_000
+  output:
+    # Taxable income = $1,001,000 - $1M = $1,000
+    # Tax = $1,000 * 9.9% = $99
+    wa_millionaires_tax: 99
+
+- name: Case 6, non-WA resident not subject to tax.
+  period: 2028
+  absolute_error_margin: 1
+  input:
+    state_code: CA
+    adjusted_gross_income: 2_000_000
+  output:
+    wa_millionaires_tax: 0
+
+- name: Case 7, charitable deduction reduces taxable income.
+  period: 2028
+  absolute_error_margin: 1
+  input:
+    state_code: WA
+    adjusted_gross_income: 2_000_000
+    charitable_cash_donations: 50_000
+  output:
+    # Taxable = $2M - $1M standard - $50K charitable = $950K
+    # Tax = $950K * 9.9% = $94,050
+    wa_millionaires_tax: 94_050
+
+- name: Case 8, charitable deduction capped at $100K.
+  period: 2028
+  absolute_error_margin: 1
+  input:
+    state_code: WA
+    adjusted_gross_income: 2_500_000
+    charitable_cash_donations: 200_000
+  output:
+    # Charitable deduction capped at $100K
+    # Taxable = $2.5M - $1M standard - $100K charitable = $1.4M
+    # Tax = $1.4M * 9.9% = $138,600
+    wa_millionaires_tax: 138_600
+
+- name: Case 9, joint filers share $1M standard deduction.
+  period: 2028
+  absolute_error_margin: 1
+  input:
+    state_code: WA
+    filing_status: JOINT
+    adjusted_gross_income: 2_000_000
+  output:
+    # Married couples share the $1M deduction (not doubled)
+    # Taxable = $2M - $1M = $1M
+    # Tax = $1M * 9.9% = $99,000
+    wa_millionaires_tax: 99_000
+
+- name: Case 10, no tax before 2028.
+  period: 2027
+  input:
+    state_code: WA
+    adjusted_gross_income: 2_000_000
+  output:
+    wa_millionaires_tax: 0
+
+- name: Case 11, non-cash charitable donations reduce taxable income.
+  period: 2028
+  absolute_error_margin: 1
+  input:
+    state_code: WA
+    adjusted_gross_income: 2_000_000
+    charitable_non_cash_donations: 75_000
+  output:
+    # Taxable = $2M - $1M standard - $75K charitable = $925K
+    # Tax = $925K * 9.9% = $91,575
+    wa_millionaires_tax: 91_575
+
+- name: Case 12, combined cash and non-cash donations capped at $100K.
+  period: 2028
+  absolute_error_margin: 1
+  input:
+    state_code: WA
+    adjusted_gross_income: 2_500_000
+    charitable_cash_donations: 80_000
+    charitable_non_cash_donations: 60_000
+  output:
+    # Charitable = $80K + $60K = $140K, capped at $100K
+    # Taxable = $2.5M - $1M standard - $100K charitable = $1.4M
+    # Tax = $1.4M * 9.9% = $138,600
+    wa_millionaires_tax: 138_600
+
+- name: Case 13, zero income.
+  period: 2028
+  input:
+    state_code: WA
+    adjusted_gross_income: 0
+  output:
+    wa_millionaires_tax: 0
+
+- name: Case 14, negative AGI from self-employment losses.
+  period: 2028
+  input:
+    state_code: WA
+    adjusted_gross_income: -500_000
+  output:
+    wa_millionaires_tax: 0
+
+- name: Case 15, charitable deduction zeroes out taxable income.
+  period: 2028
+  input:
+    state_code: WA
+    adjusted_gross_income: 1_050_000
+    charitable_cash_donations: 100_000
+  output:
+    # Taxable = $1.05M - $1M standard - $100K charitable = -$50K = $0
+    wa_millionaires_tax: 0
diff --git a/policyengine_us/tests/policy/contrib/states/wa/sb6346/sb6346.yaml b/policyengine_us/tests/policy/contrib/states/wa/sb6346/sb6346.yaml
deleted file mode 100644
index 7e99de87a02..00000000000
--- a/policyengine_us/tests/policy/contrib/states/wa/sb6346/sb6346.yaml
+++ /dev/null
@@ -1,638 +0,0 @@
-# WA SSB 6346 Income Tax Reform Tests
-# Tests the 9.9% income tax on Washington taxable income:
-#   tax = max(0, AGI - charitable_deduction - standard_deduction) * 0.099
-# Standard deduction: $1,000,000 (same for single and married)
-# Charitable deduction cap: $100,000 individual, $100,000 joint
-
-- name: Case 1, single high earner with charitable below cap.
-  period: 2028
-  absolute_error_margin: 1
-  reforms: policyengine_us.reforms.states.wa.sb6346.sb6346.wa_sb6346
-  input:
-    gov.contrib.states.wa.sb6346.in_effect: true
-    people:
-      person1:
-        age: 40
-        employment_income: 2_000_000
-        charitable_cash_donations: 50_000
-    tax_units:
-      tax_unit:
-        members: [person1]
-        filing_status: SINGLE
-    households:
-      household:
-        members: [person1]
-        state_code: WA
-  output:
-    # AGI = $2,000,000
-    wa_income_tax_base_income: 2_000_000
-    # Charitable: $50,000 < $100,000 cap -> full $50,000
-    wa_income_tax_charitable_deduction: 50_000
-    # Standard deduction: $1,000,000
-    wa_income_tax_standard_deduction: 1_000_000
-    # Taxable: $2,000,000 - $50,000 - $1,000,000 = $950,000
-    wa_income_tax_taxable_income: 950_000
-    # Tax: $950,000 * 0.099 = $94,050
-    wa_income_tax: 94_050
-
-- name: Case 2, single filer below threshold.
-  period: 2028
-  absolute_error_margin: 1
-  reforms: policyengine_us.reforms.states.wa.sb6346.sb6346.wa_sb6346
-  input:
-    gov.contrib.states.wa.sb6346.in_effect: true
-    people:
-      person1:
-        age: 40
-        employment_income: 500_000
-    tax_units:
-      tax_unit:
-        members: [person1]
-        filing_status: SINGLE
-    households:
-      household:
-        members: [person1]
-        state_code: WA
-  output:
-    # AGI = $500,000
-    # Taxable: max(0, $500,000 - $0 - $1,000,000) = $0
-    wa_income_tax_taxable_income: 0
-    # Tax: $0
-    wa_income_tax: 0
-
-- name: Case 3, married joint high earners with charitable under joint cap.
-  period: 2028
-  absolute_error_margin: 1
-  reforms: policyengine_us.reforms.states.wa.sb6346.sb6346.wa_sb6346
-  input:
-    gov.contrib.states.wa.sb6346.in_effect: true
-    people:
-      person1:
-        age: 45
-        is_tax_unit_head: true
-        employment_income: 1_500_000
-        charitable_cash_donations: 40_000
-      person2:
-        age: 43
-        is_tax_unit_spouse: true
-        employment_income: 1_500_000
-        charitable_cash_donations: 40_000
-    tax_units:
-      tax_unit:
-        members: [person1, person2]
-        filing_status: JOINT
-    households:
-      household:
-        members: [person1, person2]
-        state_code: WA
-  output:
-    # AGI = $1,500,000 + $1,500,000 = $3,000,000
-    wa_income_tax_base_income: 3_000_000
-    # Charitable: $40,000 + $40,000 = $80,000 < $100,000 joint cap
-    wa_income_tax_charitable_deduction: 80_000
-    # Standard deduction: $1,000,000
-    wa_income_tax_standard_deduction: 1_000_000
-    # Taxable: $3,000,000 - $80,000 - $1,000,000 = $1,920,000
-    wa_income_tax_taxable_income: 1_920_000
-    # Tax: $1,920,000 * 0.099 = $190,080
-    wa_income_tax: 190_080
-
-- name: Case 4, married joint below threshold.
-  period: 2028
-  absolute_error_margin: 1
-  reforms: policyengine_us.reforms.states.wa.sb6346.sb6346.wa_sb6346
-  input:
-    gov.contrib.states.wa.sb6346.in_effect: true
-    people:
-      person1:
-        age: 45
-        is_tax_unit_head: true
-        employment_income: 400_000
-      person2:
-        age: 43
-        is_tax_unit_spouse: true
-        employment_income: 400_000
-    tax_units:
-      tax_unit:
-        members: [person1, person2]
-        filing_status: JOINT
-    households:
-      household:
-        members: [person1, person2]
-        state_code: WA
-  output:
-    # AGI = $800,000 < $1,000,000 standard deduction
-    # Taxable: max(0, $800,000 - $0 - $1,000,000) = $0
-    wa_income_tax: 0
-
-- name: Case 5, single filer just above threshold with modest charitable.
-  period: 2028
-  absolute_error_margin: 1
-  reforms: policyengine_us.reforms.states.wa.sb6346.sb6346.wa_sb6346
-  input:
-    gov.contrib.states.wa.sb6346.in_effect: true
-    people:
-      person1:
-        age: 40
-        employment_income: 1_050_000
-        charitable_cash_donations: 20_000
-    tax_units:
-      tax_unit:
-        members: [person1]
-        filing_status: SINGLE
-    households:
-      household:
-        members: [person1]
-        state_code: WA
-  output:
-    # AGI = $1,050,000
-    # Charitable: $20,000 < $100,000 cap -> full $20,000
-    wa_income_tax_charitable_deduction: 20_000
-    # Taxable: $1,050,000 - $20,000 - $1,000,000 = $30,000
-    wa_income_tax_taxable_income: 30_000
-    # Tax: $30,000 * 0.099 = $2,970
-    wa_income_tax: 2_970
-
-- name: Case 6, exactly at standard deduction threshold.
-  period: 2028
-  absolute_error_margin: 1
-  reforms: policyengine_us.reforms.states.wa.sb6346.sb6346.wa_sb6346
-  input:
-    gov.contrib.states.wa.sb6346.in_effect: true
-    people:
-      person1:
-        age: 40
-        employment_income: 1_000_000
-    tax_units:
-      tax_unit:
-        members: [person1]
-        filing_status: SINGLE
-    households:
-      household:
-        members: [person1]
-        state_code: WA
-  output:
-    # AGI = $1,000,000
-    # Taxable: max(0, $1,000,000 - $0 - $1,000,000) = $0
-    wa_income_tax_taxable_income: 0
-    wa_income_tax: 0
-
-- name: Case 7, non-WA resident gets zero tax.
-  period: 2028
-  absolute_error_margin: 1
-  reforms: policyengine_us.reforms.states.wa.sb6346.sb6346.wa_sb6346
-  input:
-    gov.contrib.states.wa.sb6346.in_effect: true
-    people:
-      person1:
-        age: 40
-        employment_income: 5_000_000
-    tax_units:
-      tax_unit:
-        members: [person1]
-        filing_status: SINGLE
-    households:
-      household:
-        members: [person1]
-        state_code: CA
-  output:
-    # defined_for = StateCode.WA, so CA resident gets $0
-    wa_income_tax: 0
-
-- name: Case 8, single filer with charitable exceeding individual cap.
-  period: 2028
-  absolute_error_margin: 1
-  reforms: policyengine_us.reforms.states.wa.sb6346.sb6346.wa_sb6346
-  input:
-    gov.contrib.states.wa.sb6346.in_effect: true
-    people:
-      person1:
-        age: 40
-        employment_income: 2_000_000
-        charitable_cash_donations: 200_000
-    tax_units:
-      tax_unit:
-        members: [person1]
-        filing_status: SINGLE
-    households:
-      household:
-        members: [person1]
-        state_code: WA
-  output:
-    # AGI = $2,000,000
-    wa_income_tax_base_income: 2_000_000
-    # Charitable: $200,000 > $100,000 individual cap -> capped at $100,000
-    wa_income_tax_charitable_deduction: 100_000
-    # Standard deduction: $1,000,000
-    wa_income_tax_standard_deduction: 1_000_000
-    # Taxable: $2,000,000 - $100,000 - $1,000,000 = $900,000
-    wa_income_tax_taxable_income: 900_000
-    # Tax: $900,000 * 0.099 = $89,100
-    wa_income_tax: 89_100
-
-- name: Case 9, WFTC age expansion - single age 22, no children, $10,000 earnings.
-  period: 2029
-  absolute_error_margin: 10
-  reforms: policyengine_us.reforms.states.wa.sb6346.sb6346.wa_sb6346
-  input:
-    gov.contrib.states.wa.sb6346.in_effect: true
-    people:
-      person1:
-        age: 22
-        employment_income: 10_000
-    tax_units:
-      tax_unit:
-        members: [person1]
-        filing_status: SINGLE
-    households:
-      household:
-        members: [person1]
-        state_code: WA
-  output:
-    # Age 22 < 25 so no federal EITC, but SSB 6346 expands WFTC to age 18+.
-    # With $10,000 earned income and 0 children, should receive the maximum WFTC for childless filers.
-    wa_working_families_tax_credit: 367
-
-- name: Case 10, WFTC age expansion - single age 22, no children, $0 earnings.
-  period: 2029
-  absolute_error_margin: 1
-  reforms: policyengine_us.reforms.states.wa.sb6346.sb6346.wa_sb6346
-  input:
-    gov.contrib.states.wa.sb6346.in_effect: true
-    people:
-      person1:
-        age: 22
-        employment_income: 0
-    tax_units:
-      tax_unit:
-        members: [person1]
-        filing_status: SINGLE
-    households:
-      household:
-        members: [person1]
-        state_code: WA
-  output:
-    # No earned income -> not eligible for WFTC even with age expansion.
-    wa_working_families_tax_credit: 0
-
-- name: Case 11, WFTC existing path - single age 30, no children, $15,000 earnings.
-  period: 2029
-  absolute_error_margin: 10
-  reforms: policyengine_us.reforms.states.wa.sb6346.sb6346.wa_sb6346
-  input:
-    gov.contrib.states.wa.sb6346.in_effect: true
-    people:
-      person1:
-        age: 30
-        employment_income: 15_000
-    tax_units:
-      tax_unit:
-        members: [person1]
-        filing_status: SINGLE
-    households:
-      household:
-        members: [person1]
-        state_code: WA
-  output:
-    # Age 30 qualifies for federal EITC (age 25-64), earned income > 0.
-    # Should receive WFTC via the existing EITC-eligible path.
-    wa_working_families_tax_credit: 367
-
-- name: Case 12, married joint filer with charitable exceeding joint cap.
-  period: 2028
-  absolute_error_margin: 1
-  reforms: policyengine_us.reforms.states.wa.sb6346.sb6346.wa_sb6346
-  input:
-    gov.contrib.states.wa.sb6346.in_effect: true
-    people:
-      person1:
-        age: 45
-        is_tax_unit_head: true
-        employment_income: 1_500_000
-        charitable_cash_donations: 60_000
-      person2:
-        age: 43
-        is_tax_unit_spouse: true
-        employment_income: 1_500_000
-        charitable_cash_donations: 60_000
-    tax_units:
-      tax_unit:
-        members: [person1, person2]
-        filing_status: JOINT
-    households:
-      household:
-        members: [person1, person2]
-        state_code: WA
-  output:
-    # Charitable: $60,000 + $60,000 = $120,000 > $100,000 joint cap.
-    wa_income_tax_charitable_deduction: 100_000
-    # Taxable: $3,000,000 - $100,000 - $1,000,000 = $1,900,000
-    wa_income_tax_taxable_income: 1_900_000
-    # Tax: $1,900,000 * 0.099 = $188,100
-    wa_income_tax: 188_100
-
-- name: Case 13, WFTC age expansion - single age 17, no children, $10,000 earnings.
-  period: 2029
-  absolute_error_margin: 1
-  reforms: policyengine_us.reforms.states.wa.sb6346.sb6346.wa_sb6346
-  input:
-    gov.contrib.states.wa.sb6346.in_effect: true
-    people:
-      person1:
-        age: 17
-        employment_income: 10_000
-    tax_units:
-      tax_unit:
-        members: [person1]
-        filing_status: SINGLE
-    households:
-      household:
-        members: [person1]
-        state_code: WA
-  output:
-    # Age 17 is below the SSB 6346 minimum age threshold.
-    wa_working_families_tax_credit: 0
-
-- name: Case 14, WFTC age expansion - single age 18, no children, $10,000 earnings.
-  period: 2029
-  absolute_error_margin: 10
-  reforms: policyengine_us.reforms.states.wa.sb6346.sb6346.wa_sb6346
-  input:
-    gov.contrib.states.wa.sb6346.in_effect: true
-    people:
-      person1:
-        age: 18
-        employment_income: 10_000
-    tax_units:
-      tax_unit:
-        members: [person1]
-        filing_status: SINGLE
-    households:
-      household:
-        members: [person1]
-        state_code: WA
-  output:
-    # Age 18 qualifies for the SSB 6346 WFTC expansion.
-    wa_working_families_tax_credit: 367
-
-- name: Case 15, reform toggle off leaves WA income tax unchanged.
-  period: 2028
-  absolute_error_margin: 1
-  reforms: policyengine_us.reforms.states.wa.sb6346.sb6346.wa_sb6346
-  input:
-    gov.contrib.states.wa.sb6346.in_effect: false
-    people:
-      person1:
-        age: 40
-        employment_income: 2_000_000
-    tax_units:
-      tax_unit:
-        members: [person1]
-        filing_status: SINGLE
-    households:
-      household:
-        members: [person1]
-        state_code: WA
-  output:
-    wa_income_tax: 0
-
-- name: Case 16, WFTC spouse age expansion - head under 18, spouse 22, joint filers.
-  period: 2029
-  absolute_error_margin: 10
-  reforms: policyengine_us.reforms.states.wa.sb6346.sb6346.wa_sb6346
-  input:
-    gov.contrib.states.wa.sb6346.in_effect: true
-    people:
-      person1:
-        age: 16
-        is_tax_unit_head: true
-        employment_income: 5_000
-      person2:
-        age: 22
-        is_tax_unit_spouse: true
-        employment_income: 5_000
-    tax_units:
-      tax_unit:
-        members: [person1, person2]
-        filing_status: JOINT
-    households:
-      household:
-        members: [person1, person2]
-        state_code: WA
-  output:
-    # Head age 16 < 18 and both < 25 so no federal EITC.
-    # SSB 6346 expansion: age_spouse (22) >= min_age (18) -> eligible.
-    # Combined earned income = $10,000, 0 children -> childless maximum WFTC.
-    wa_working_families_tax_credit: 367
-
-- name: Case 17, non-cash charitable donations capped at individual limit.
-  period: 2028
-  absolute_error_margin: 1
-  reforms: policyengine_us.reforms.states.wa.sb6346.sb6346.wa_sb6346
-  input:
-    gov.contrib.states.wa.sb6346.in_effect: true
-    people:
-      person1:
-        age: 40
-        employment_income: 1_500_000
-        charitable_non_cash_donations: 150_000
-    tax_units:
-      tax_unit:
-        members: [person1]
-        filing_status: SINGLE
-    households:
-      household:
-        members: [person1]
-        state_code: WA
-  output:
-    # AGI = $1,500,000
-    wa_income_tax_base_income: 1_500_000
-    # Non-cash charitable: $150,000 > $100,000 individual cap -> capped at $100,000
-    wa_income_tax_charitable_deduction: 100_000
-    # Standard deduction: $1,000,000
-    wa_income_tax_standard_deduction: 1_000_000
-    # Taxable: $1,500,000 - $100,000 - $1,000,000 = $400,000
-    wa_income_tax_taxable_income: 400_000
-    # Tax: $400,000 * 0.099 = $39,600
-    wa_income_tax: 39_600
-
-- name: Case 18, capital gains combined with SSB 6346 income tax.
-  period: 2028
-  absolute_error_margin: 0.01
-  reforms: policyengine_us.reforms.states.wa.sb6346.sb6346.wa_sb6346
-  input:
-    gov.contrib.states.wa.sb6346.in_effect: true
-    people:
-      person1:
-        age: 40
-        employment_income: 2_000_000
-        long_term_capital_gains: 1_500_000
-    tax_units:
-      tax_unit:
-        members: [person1]
-        filing_status: SINGLE
-    households:
-      household:
-        members: [person1]
-        state_code: WA
-  output:
-    # AGI includes employment + LTCG = $3,500,000
-    wa_income_tax_base_income: 3_500_000
-    # SSB 6346 taxable: $3,500,000 - $0 charitable - $1,000,000 std = $2,500,000
-    wa_income_tax_taxable_income: 2_500_000
-    # SSB 6346 income tax: $2,500,000 * 0.099 = $247,500
-    # WA capital gains tax on the same return is $89,998 in 2028 under current parameters.
-    wa_capital_gains_tax: 89_998
-    # before_credits = $247,500 + $89,998 = $337,498
-    wa_income_tax_before_refundable_credits: 337_498
-    # WFTC = $0 (income far above EITC limit)
-    # wa_income_tax = before_credits - 0 = before_credits
-    wa_income_tax: 337_498
-
-- name: Case 19, negative AGI floors taxable income and tax at zero.
-  period: 2029
-  absolute_error_margin: 1
-  reforms: policyengine_us.reforms.states.wa.sb6346.sb6346.wa_sb6346
-  input:
-    gov.contrib.states.wa.sb6346.in_effect: true
-    people:
-      person1:
-        age: 40
-        self_employment_income: -500_000
-    tax_units:
-      tax_unit:
-        members: [person1]
-        filing_status: SINGLE
-    households:
-      household:
-        members: [person1]
-        state_code: WA
-  output:
-    # AGI is negative from self-employment losses
-    # Taxable: max(0, negative_AGI - deductions) = 0
-    wa_income_tax_taxable_income: 0
-    # Tax: 0 (no tax on negative/zero income)
-    wa_income_tax: 0
-
-- name: Case 20, WFTC offsets WA income tax when refundable credits are smaller than tax due.
-  period: 2029
-  absolute_error_margin: 10
-  reforms: policyengine_us.reforms.states.wa.sb6346.sb6346.wa_sb6346
-  input:
-    gov.contrib.states.wa.sb6346.in_effect: true
-    people:
-      person1:
-        age: 22
-        employment_income: 10_000
-    tax_units:
-      tax_unit:
-        members: [person1]
-        filing_status: SINGLE
-        wa_capital_gains_tax: 500
-    households:
-      household:
-        members: [person1]
-        state_code: WA
-  output:
-    # Base income is below the $1M standard deduction, so SSB 6346 tax is $0.
-    wa_income_tax_taxable_income: 0
-    # A direct capital gains tax input creates positive WA tax before refundable credits.
-    wa_income_tax_before_refundable_credits: 500
-    # Age 22 + earned income triggers the expanded WFTC path.
-    wa_working_families_tax_credit: 367
-    # Final WA income tax remains positive because tax due exceeds the refundable credit.
-    wa_income_tax: 133.3
-
-- name: Case 21, WFTC age expansion does not apply in 2028.
-  period: 2028
-  absolute_error_margin: 1
-  reforms: policyengine_us.reforms.states.wa.sb6346.sb6346.wa_sb6346
-  input:
-    gov.contrib.states.wa.sb6346.in_effect: true
-    people:
-      person1:
-        age: 22
-        employment_income: 10_000
-    tax_units:
-      tax_unit:
-        members: [person1]
-        filing_status: SINGLE
-    households:
-      household:
-        members: [person1]
-        state_code: WA
-  output:
-    # The income tax reform is active in 2028, but the WFTC age expansion is not.
-    wa_working_families_tax_credit: 0
-
-- name: Case 22, WFTC can exceed WA tax owed and produce a negative net tax.
-  period: 2029
-  absolute_error_margin: 10
-  reforms: policyengine_us.reforms.states.wa.sb6346.sb6346.wa_sb6346
-  input:
-    gov.contrib.states.wa.sb6346.in_effect: true
-    people:
-      person1:
-        age: 22
-        employment_income: 10_000
-    tax_units:
-      tax_unit:
-        members: [person1]
-        filing_status: SINGLE
-    households:
-      household:
-        members: [person1]
-        state_code: WA
-  output:
-    # No SSB 6346 income tax is due below the $1M standard deduction.
-    wa_income_tax_before_refundable_credits: 0
-    # The expanded WFTC remains refundable when it exceeds tax owed.
-    wa_working_families_tax_credit: 367
-    wa_income_tax: -367
-
-- name: Case 23, head of household uses the individual charitable deduction cap.
-  period: 2028
-  absolute_error_margin: 1
-  reforms: policyengine_us.reforms.states.wa.sb6346.sb6346.wa_sb6346
-  input:
-    gov.contrib.states.wa.sb6346.in_effect: true
-    people:
-      person1:
-        age: 40
-        employment_income: 2_000_000
-        charitable_cash_donations: 150_000
-    tax_units:
-      tax_unit:
-        members: [person1]
-        filing_status: HEAD_OF_HOUSEHOLD
-    households:
-      household:
-        members: [person1]
-        state_code: WA
-  output:
-    wa_income_tax_charitable_deduction: 100_000
-    wa_income_tax_taxable_income: 900_000
-    wa_income_tax: 89_100
-
-- name: Case 24, one dollar above the standard deduction threshold.
-  period: 2028
-  absolute_error_margin: 0.01
-  reforms: policyengine_us.reforms.states.wa.sb6346.sb6346.wa_sb6346
-  input:
-    gov.contrib.states.wa.sb6346.in_effect: true
-    people:
-      person1:
-        age: 40
-        employment_income: 1_000_001
-    tax_units:
-      tax_unit:
-        members: [person1]
-        filing_status: SINGLE
-    households:
-      household:
-        members: [person1]
-        state_code: WA
-  output:
-    wa_income_tax_taxable_income: 1
-    wa_income_tax_before_refundable_credits: 0.099
-    wa_income_tax: 0.099
diff --git a/policyengine_us/variables/gov/states/wa/tax/income/credits/wa_working_families_tax_credit.py b/policyengine_us/variables/gov/states/wa/tax/income/credits/wa_working_families_tax_credit.py
index 2d75d6bf2c4..4a4a40d95e6 100644
--- a/policyengine_us/variables/gov/states/wa/tax/income/credits/wa_working_families_tax_credit.py
+++ b/policyengine_us/variables/gov/states/wa/tax/income/credits/wa_working_families_tax_credit.py
@@ -7,13 +7,24 @@ class wa_working_families_tax_credit(Variable):
     label = "Washington Working Families Tax Credit"
     unit = USD
     definition_period = YEAR
-    reference = "https://app.leg.wa.gov/RCW/default.aspx?cite=82.08.0206"
+    reference = (
+        "https://app.leg.wa.gov/RCW/default.aspx?cite=82.08.0206",
+        "https://lawfilesext.leg.wa.gov/biennium/2025-26/Pdf/Bills/Senate%20Passed%20Legislature/6346-S.PL.pdf#page=61",
+    )
     defined_for = StateCode.WA
 
     def formula(tax_unit, period, parameters):
-        # Filers must claim EITC and be in Washington to be eligible.
-        # TODO: Include ITIN children.
-        eligible = tax_unit("eitc", period) > 0
+        # Baseline eligibility: filers who claim EITC
+        eitc = tax_unit("eitc", period)
+        eitc_eligible = eitc > 0
+
+        # ESSB 6346 Sec. 901: age expansion eligibility (effective 2029)
+        age_expansion_eligible = tax_unit(
+            "wa_working_families_tax_credit_age_expansion_eligible", period
+        )
+
+        eligible = eitc_eligible | age_expansion_eligible
+
         # Parameters are based on EITC-eligible children.
         p = parameters(
             period
diff --git a/policyengine_us/variables/gov/states/wa/tax/income/credits/wa_working_families_tax_credit_age_expansion_eligible.py b/policyengine_us/variables/gov/states/wa/tax/income/credits/wa_working_families_tax_credit_age_expansion_eligible.py
new file mode 100644
index 00000000000..3b64958fdd5
--- /dev/null
+++ b/policyengine_us/variables/gov/states/wa/tax/income/credits/wa_working_families_tax_credit_age_expansion_eligible.py
@@ -0,0 +1,26 @@
+from policyengine_us.model_api import *
+
+
+class wa_working_families_tax_credit_age_expansion_eligible(Variable):
+    value_type = bool
+    entity = TaxUnit
+    label = "Eligible for Washington Working Families Tax Credit via age expansion"
+    definition_period = YEAR
+    reference = "https://lawfilesext.leg.wa.gov/biennium/2025-26/Pdf/Bills/Senate%20Passed%20Legislature/6346-S.PL.pdf#page=61"
+    defined_for = StateCode.WA
+
+    def formula(tax_unit, period, parameters):
+        # ESSB 6346 Sec. 901(2)(a)(ii)(D): individuals who do not meet the
+        # EITC age requirement but are at least age 18 (effective 2029).
+        p = parameters(
+            period
+        ).gov.states.wa.tax.income.credits.working_families_tax_credit.age_expansion
+
+        expansion_in_effect = p.in_effect
+        age_head = tax_unit("age_head", period)
+        age_spouse = tax_unit("age_spouse", period)
+        filer_meets_min_age = (age_head >= p.min_age) | (age_spouse >= p.min_age)
+        earned_income = tax_unit("filer_adjusted_earnings", period)
+        has_earned_income = earned_income > 0
+
+        return expansion_in_effect & filer_meets_min_age & has_earned_income
diff --git a/policyengine_us/variables/gov/states/wa/tax/income/millionaires_tax/wa_millionaires_tax.py b/policyengine_us/variables/gov/states/wa/tax/income/millionaires_tax/wa_millionaires_tax.py
new file mode 100644
index 00000000000..239e71eeb91
--- /dev/null
+++ b/policyengine_us/variables/gov/states/wa/tax/income/millionaires_tax/wa_millionaires_tax.py
@@ -0,0 +1,16 @@
+from policyengine_us.model_api import *
+
+
+class wa_millionaires_tax(Variable):
+    value_type = float
+    entity = TaxUnit
+    label = "Washington millionaires tax"
+    unit = USD
+    definition_period = YEAR
+    reference = "https://lawfilesext.leg.wa.gov/biennium/2025-26/Pdf/Bills/Senate%20Passed%20Legislature/6346-S.PL.pdf#page=8"
+    defined_for = "wa_millionaires_tax_applies"
+
+    def formula(tax_unit, period, parameters):
+        p = parameters(period).gov.states.wa.tax.income.millionaires_tax
+        taxable_income = tax_unit("wa_millionaires_tax_taxable_income", period)
+        return taxable_income * p.rate
diff --git a/policyengine_us/variables/gov/states/wa/tax/income/millionaires_tax/wa_millionaires_tax_applies.py b/policyengine_us/variables/gov/states/wa/tax/income/millionaires_tax/wa_millionaires_tax_applies.py
new file mode 100644
index 00000000000..b4876a44716
--- /dev/null
+++ b/policyengine_us/variables/gov/states/wa/tax/income/millionaires_tax/wa_millionaires_tax_applies.py
@@ -0,0 +1,13 @@
+from policyengine_us.model_api import *
+
+
+class wa_millionaires_tax_applies(Variable):
+    value_type = bool
+    entity = TaxUnit
+    label = "Washington millionaires tax applies"
+    definition_period = YEAR
+    reference = "https://lawfilesext.leg.wa.gov/biennium/2025-26/Pdf/Bills/Senate%20Passed%20Legislature/6346-S.PL.pdf#page=8"
+    defined_for = StateCode.WA
+
+    def formula(tax_unit, period, parameters):
+        return parameters(period).gov.states.wa.tax.income.millionaires_tax.in_effect
diff --git a/policyengine_us/variables/gov/states/wa/tax/income/millionaires_tax/wa_millionaires_tax_base_income.py b/policyengine_us/variables/gov/states/wa/tax/income/millionaires_tax/wa_millionaires_tax_base_income.py
new file mode 100644
index 00000000000..86380eae623
--- /dev/null
+++ b/policyengine_us/variables/gov/states/wa/tax/income/millionaires_tax/wa_millionaires_tax_base_income.py
@@ -0,0 +1,15 @@
+from policyengine_us.model_api import *
+
+
+class wa_millionaires_tax_base_income(Variable):
+    value_type = float
+    entity = TaxUnit
+    label = "Washington millionaires tax base income"
+    unit = USD
+    definition_period = YEAR
+    reference = (
+        "https://lawfilesext.leg.wa.gov/biennium/2025-26/Pdf/Bills/Senate%20Passed%20Legislature/6346-S.PL.pdf#page=7",
+        "https://lawfilesext.leg.wa.gov/biennium/2025-26/Pdf/Bills/Senate%20Passed%20Legislature/6346-S.PL.pdf#page=11",
+    )
+    defined_for = "wa_millionaires_tax_applies"
+    adds = ["adjusted_gross_income"]
diff --git a/policyengine_us/variables/gov/states/wa/tax/income/millionaires_tax/wa_millionaires_tax_charitable_deduction.py b/policyengine_us/variables/gov/states/wa/tax/income/millionaires_tax/wa_millionaires_tax_charitable_deduction.py
new file mode 100644
index 00000000000..4987d82daf0
--- /dev/null
+++ b/policyengine_us/variables/gov/states/wa/tax/income/millionaires_tax/wa_millionaires_tax_charitable_deduction.py
@@ -0,0 +1,20 @@
+from policyengine_us.model_api import *
+
+
+class wa_millionaires_tax_charitable_deduction(Variable):
+    value_type = float
+    entity = TaxUnit
+    label = "Washington millionaires tax charitable deduction"
+    unit = USD
+    definition_period = YEAR
+    reference = "https://lawfilesext.leg.wa.gov/biennium/2025-26/Pdf/Bills/Senate%20Passed%20Legislature/6346-S.PL.pdf#page=14"
+    defined_for = "wa_millionaires_tax_applies"
+
+    def formula(tax_unit, period, parameters):
+        p = parameters(period).gov.states.wa.tax.income.millionaires_tax
+        charitable = add(
+            tax_unit,
+            period,
+            ["charitable_cash_donations", "charitable_non_cash_donations"],
+        )
+        return min_(charitable, p.deductions.charitable.cap)
diff --git a/policyengine_us/variables/gov/states/wa/tax/income/millionaires_tax/wa_millionaires_tax_standard_deduction.py b/policyengine_us/variables/gov/states/wa/tax/income/millionaires_tax/wa_millionaires_tax_standard_deduction.py
new file mode 100644
index 00000000000..91ddcf04819
--- /dev/null
+++ b/policyengine_us/variables/gov/states/wa/tax/income/millionaires_tax/wa_millionaires_tax_standard_deduction.py
@@ -0,0 +1,15 @@
+from policyengine_us.model_api import *
+
+
+class wa_millionaires_tax_standard_deduction(Variable):
+    value_type = float
+    entity = TaxUnit
+    label = "Washington millionaires tax standard deduction"
+    unit = USD
+    definition_period = YEAR
+    reference = "https://lawfilesext.leg.wa.gov/biennium/2025-26/Pdf/Bills/Senate%20Passed%20Legislature/6346-S.PL.pdf#page=13"
+    defined_for = "wa_millionaires_tax_applies"
+
+    def formula(tax_unit, period, parameters):
+        p = parameters(period).gov.states.wa.tax.income.millionaires_tax
+        return p.deductions.standard
diff --git a/policyengine_us/variables/gov/states/wa/tax/income/millionaires_tax/wa_millionaires_tax_taxable_income.py b/policyengine_us/variables/gov/states/wa/tax/income/millionaires_tax/wa_millionaires_tax_taxable_income.py
new file mode 100644
index 00000000000..0af55e6618f
--- /dev/null
+++ b/policyengine_us/variables/gov/states/wa/tax/income/millionaires_tax/wa_millionaires_tax_taxable_income.py
@@ -0,0 +1,23 @@
+from policyengine_us.model_api import *
+
+
+class wa_millionaires_tax_taxable_income(Variable):
+    value_type = float
+    entity = TaxUnit
+    label = "Washington millionaires tax taxable income"
+    unit = USD
+    definition_period = YEAR
+    reference = (
+        "https://lawfilesext.leg.wa.gov/biennium/2025-26/Pdf/Bills/Senate%20Passed%20Legislature/6346-S.PL.pdf#page=7",
+        "https://lawfilesext.leg.wa.gov/biennium/2025-26/Pdf/Bills/Senate%20Passed%20Legislature/6346-S.PL.pdf#page=14",
+        "https://lawfilesext.leg.wa.gov/biennium/2025-26/Pdf/Bills/Senate%20Passed%20Legislature/6346-S.PL.pdf#page=15",
+    )
+    defined_for = "wa_millionaires_tax_applies"
+
+    def formula(tax_unit, period, parameters):
+        base_income = tax_unit("wa_millionaires_tax_base_income", period)
+        charitable_deduction = tax_unit(
+            "wa_millionaires_tax_charitable_deduction", period
+        )
+        standard_deduction = tax_unit("wa_millionaires_tax_standard_deduction", period)
+        return max_(base_income - charitable_deduction - standard_deduction, 0)
diff --git a/policyengine_us/variables/gov/states/wa/tax/income/wa_income_tax_before_refundable_credits.py b/policyengine_us/variables/gov/states/wa/tax/income/wa_income_tax_before_refundable_credits.py
index dc5ddc2247c..6428f1aa831 100644
--- a/policyengine_us/variables/gov/states/wa/tax/income/wa_income_tax_before_refundable_credits.py
+++ b/policyengine_us/variables/gov/states/wa/tax/income/wa_income_tax_before_refundable_credits.py
@@ -8,4 +8,4 @@ class wa_income_tax_before_refundable_credits(Variable):
     unit = USD
     definition_period = YEAR
     defined_for = StateCode.WA
-    adds = ["wa_capital_gains_tax"]
+    adds = ["wa_capital_gains_tax", "wa_millionaires_tax"]