Is Washington's capital gains tax really an "excise tax"?

Yes — Washington characterizes it as an excise tax on the sale or exchange of capital assets, not an income tax. This distinction was central to the legal challenge: Washington's constitution prohibits a graduated income tax, but a flat excise tax is permissible. The Washington Supreme Court upheld the tax in Quinn v. State of Washington (March 2023), ruling it is constitutionally valid as an excise tax.

Why is real estate completely exempt from the WA capital gains tax?

Real estate was specifically excluded from the WA capital gains tax in the original legislation (SB 5096). This is likely a combination of political considerations (housing affordability concerns) and recognition that real estate already bears significant property taxes. All types of real property are exempt — including investment and commercial real estate, not just primary residences.

Is the WA capital gains tax deductible on federal returns?

No. Because it is classified as an excise tax (not an income tax), it is not deductible as a state income tax on your federal Schedule A. Since the SALT deduction is already capped at $40,000 in 2025 for most filers, this limitation is most relevant for taxpayers who itemize and haven't used their SALT cap on property taxes and state income taxes.

Does the $270,000 standard deduction apply per person or per couple?

The standard deduction applies per return, not per person. For married couples filing jointly on their Washington return, the deduction is $270,000 for the return — not $540,000. Washington does not have a separate tax return, so the deduction is applied on the federal-like annual capital gains return filed with the WA Department of Revenue.

What happens to WA capital gains when you move out of Washington?

If you sell an asset while a Washington resident, the gain is subject to WA capital gains tax. If you move out of WA before selling, you generally owe no WA capital gains tax, though specific facts matter. The timing of the sale relative to residency is important for planning large exits.

Tax

Washington State Capital Gains Tax Calculator 2025 — 7% on LTCG Above $270K

Calculate Washington State's 7% capital gains excise tax on long-term gains above $270,000 (estimated 2025 threshold). Real estate is completely exempt. Upheld by WA Supreme Court in March 2023.

By The FinCalc TeamUpdated May 31, 2026

Washington State has no income tax — but since 2022, it imposes a 7% capital gains excise tax on long-term capital gains above a standard deduction (estimated $270,000 for 2025, inflation-adjusted from $250,000). The tax was upheld by the Washington Supreme Court in March 2023. Real estate is completely exempt — Washington's most significant exemption. Gains inside retirement accounts are exempt as well. For Washington residents with large stock portfolios or business sales, this 7% flat tax can add substantially to the federal capital gains burden, especially for gains above $270,000.

How Washington State Capital Gains Tax Is Calculated

Washington's capital gains excise tax is a flat 7% on net long-term gains above the standard deduction:

Step 1 — Identify gross long-term capital gains:

Total LTCG = All gains on assets held > 1 year
             (Short-term gains are NOT subject to WA CG tax)

Step 2 — Subtract exempt gains:

Net LTCG = Total LTCG
         − Real estate gains (all types — fully exempt)
         − Retirement account gains (401k, IRA, etc.)
         − Other exempt gains (timber, farming, small business)

Step 3 — Apply the standard deduction:

Taxable gains = max(0, Net LTCG − $270,000 standard deduction)

Step 4 — Apply the 7% flat rate:

WA CG Tax = Taxable gains × 7%

Key exemptions — who this tax most affects:

Investors with large stock/ETF portfolios above $270K in annual gains
Startup founders and executives with large equity grants (not real estate)
People selling businesses (non-real-estate business interests)
Taxpayers who don't have large real estate gains to offset

When to Use This Calculator

Use this calculator when:

Planning a large stock sale — If you're selling a concentrated position, exercising stock options, or realizing gains on a brokerage account, quantify the WA capital gains tax cost before executing the trade.
Evaluating installment sales — Spreading a large business sale over multiple years can keep annual gains below $270,000, eliminating the WA capital gains tax entirely. Model the year-by-year tax impact.
Comparing WA vs. other states — Washington has no income tax but a 7% capital gains tax. Compare the total tax burden (federal + state) for Washington vs. a state with a lower capital gains rate but higher income tax.
Timing equity compensation exercises — For startup employees or public company executives with RSUs or stock options, timing your exercises and sales to stay under the $270,000 threshold can eliminate the WA capital gains tax.
Confirming real estate exemptions — Before assuming your real estate sale is exempt, verify the property qualifies. All Washington real property gains are exempt — use this calculator to confirm the impact.

Understanding the Inputs

Total Long-Term Capital Gains: Your total federal long-term capital gains (assets held more than one year) before any Washington-specific exemptions. Short-term capital gains are not subject to the WA capital gains tax. Enter the gross gain before the standard deduction — the calculator applies the threshold.
Real Estate Gains (Exempt): Washington explicitly exempts all real property (real estate) gains from the capital gains excise tax — any type: primary residence, rental property, investment property, commercial real estate, undeveloped land. This is the largest exemption for most taxpayers. Enter the long-term gain portion from real estate sales.
Retirement Account Gains (Exempt): Gains on assets held inside qualifying retirement accounts (401k, IRA, 403b, pension plans, SEP-IRA, SIMPLE IRA) are exempt. In practice, gains inside these accounts are generally ordinary income when distributed — not capital gains — so this field is primarily for clarifying amounts that shouldn't be counted as WA capital gains.
Other Exempt Gains (Timber, Farm, Business): Additional Washington exemptions include: gains from the sale of timber and timberlands, livestock and other farming assets, commercial fishing licenses, goodwill from selling a qualified small business (fewer than 5 employees), and condemnation or involuntary conversion proceeds. Enter the applicable exempt amount here.

Frequently Asked Questions

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The FinCalc Team

Personal Finance Experts

The FinCalc team is a group of personal finance writers, analysts, and engineers dedicated to building accurate, transparent financial calculators. Every formula is verified against industry standards and explained in plain language.

Last reviewed and updated: May 31, 2026