$167,580 difference over 30 yearsFor an identical retiree (age 60, $2M, 60/40, $80K real spend), QuantCalc's Monte Carlo study found a median 30-year state-tax gap of $167,580 between California and Washington — Washington is the cheaper state. That money stays invested, which is why Washington's median terminal balance is higher.
California vs Washington at a glance
| Factor | California | Washington |
|---|---|---|
| State income tax | 13.30% top | None |
| Taxes Social Security | No | No |
| Taxes 401(k)/IRA | Yes | No |
| State estate/inheritance tax | No | Yes |
| Tax on $100k withdrawal | $13,300/yr | $0/yr |
| Retirement-friendliness | high tax | tax free |
| 30-yr median state tax (MC) | $167,580 | $0 |
| 30-yr success rate (MC) | 67.91% (#51) | 76.49% (#6) |
| Median terminal balance (MC) | $652,555 | $1,017,593 |
The income-tax difference, year by year
The simplest way to see the gap: on a steady $100,000 annual retirement withdrawal, California collects about $13,300 in state income tax and Washington collects about $0 — a difference of roughly $13,300 every year. Highest top marginal rate in the u.s., 1% mental-health surcharge over $1m. No income tax (but new 7% capital gains tax over $262k), $2.193m estate exemption.
Over a 30-year retirement, QuantCalc's Monte Carlo simulation (identical portfolio and spending in both states, only the tax code changes) puts the median lifetime state-tax difference at $167,580 — and because the saved tax stays invested and compounds, Washington's median ending balance is the higher of the two.
Beyond income tax
State income tax is only part of the retirement-cost picture. When comparing California and Washington, also weigh:
- Property tax — a tax-free-income state can still have high property tax; factor your home value.
- Sales tax — affects every dollar you spend, not just income.
- Estate / inheritance tax — California: none; Washington: has one. Matters for larger estates.
- Roth conversion cost — converting in the lower-income-tax state of the two cuts the state tax on each converted dollar. See conversion-tax scenarios.
See California vs Washington on your full plan
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Deep-dive either state: California retirement tax guide · Washington retirement tax guide. Or see the full 50-state comparison and the 51-state Monte Carlo study.
FAQ
Is California or Washington better for retirement taxes?
On state income tax, Washington is the lighter-tax state. In QuantCalc's 30-year Monte Carlo study, a representative retiree paid a median of $0 in state tax in Washington versus $167,580 in the other — a $167,580 lifetime difference on identical income and spending.
Does California tax Social Security and 401(k) withdrawals?
California does not tax Social Security benefits and taxes 401(k)/traditional IRA distributions at the state level. Highest top marginal rate in the u.s., 1% mental-health surcharge over $1m.
Does Washington tax Social Security and 401(k) withdrawals?
Washington does not tax Social Security benefits and exempts 401(k)/traditional IRA distributions at the state level. No income tax (but new 7% capital gains tax over $262k), $2.193m estate exemption.
How much would moving from California to Washington save on retirement taxes?
On a $100,000 annual withdrawal, the state income tax is about $13,300 in California versus $0 in Washington — roughly $13,300 per year of difference. Over 30 years, the Monte Carlo median gap was $167,580. Don't forget property tax, sales tax, and estate tax also differ — see the table above.
Last updated 2026-06-02. State tax data 2026 (Tax Foundation + state DoR). Monte Carlo figures from the QuantCalc 51-state study (2026-05-12, CC-BY-4.0): identical age-60 / $2M / 60-40 / $80K-real-spend retiree in each state. Educational only, not tax advice.