QSBS in Washington State: Conformity, the 9.9% Capital Gains Tax, and the 2026 Legislative Threat

How Washington State currently treats QSBS gains

Washington does not have a personal income tax. In 2021, the legislature enacted a capital gains excise tax (SB 5096), which Washington's Supreme Court upheld in 2023.¹ The tax applies to net long-term capital gains above an annually adjusted standard deduction — $270,000 in 2024, $278,000 in 2025, with subsequent years adjusted for CPI.

Critically, Washington computes the tax starting from the taxpayer's federal long-term capital gain as reported on the federal return. Gains excluded under Section 1202 are excluded before the federal return is finalized — they never appear in the federal LTCG figure. Because Washington's starting point is that same number, Section 1202-excluded gain is simply not in Washington's tax base. No conformity legislation was required; the exclusion flows through automatically.

The OBBBA enhancements — the $15 million exclusion cap, tiered 3/4/5-year holding periods, and $75 million gross assets threshold for stock issued after July 4, 2025 — also flow through to Washington without any state legislation. Because the OBBBA changed the federal LTCG treatment for qualifying stock, and Washington starts from that federal figure, Washington founders with post-July 2025 QSBS get the enhanced exclusion at the state level automatically. This differs from Massachusetts, which uses a static IRC reference date and may not recognize OBBBA enhancements for state purposes.

Washington's capital gains tax structure and what QSBS exclusion is worth

Washington's capital gains excise tax applies a tiered rate structure, modified in 2025 by SB 5813 (signed May 20, 2025, retroactive to January 1, 2025):²

Real estate sales and gains in qualified retirement accounts are exempt from the tax. Qualified family-owned small business sales have a separate deduction. Charitable donations of appreciated assets can reduce the taxable base.

For a Washington founder with a large QSBS exit, the state-level value of the Section 1202 exclusion is significant because virtually all of a material liquidity event exceeds $1 million in total gain — meaning the 9.9% rate applies to nearly all of the taxable amount that would remain without an exclusion.

The Section 1202 exclusion is worth approximately $5 million in combined tax on a $15 million exit for a Washington founder — roughly $1.4 million in state capital gains tax plus the federal savings. For a Seattle-area founder who has spent their career watching California founders lose 13.3% at the state level, the conformity gap is a meaningful advantage worth preserving.

The 2026 legislative threat: SB 6229 and HB 2292

In January 2026, two bills were introduced in the Washington State Legislature that would have explicitly added Section 1202-excluded gains back to the Washington capital gains tax base:³

• SB 6229 — introduced by Senator Noel Frame in the Senate Ways & Means Committee
• HB 2292 — introduced by Representative April Berg, with co-sponsors including Reps. My-Linh Thai, Janice Zahn, Davina Duerr, and Kristine Reeves in the House Finance Committee

Both bills held public hearings on January 27, 2026. Startup founders, venture investors, and tech-industry trade groups testified heavily against the measures, citing Washington's emerging startup ecosystem and the risk of founder departures. Both bills died when the session ended without advancing out of committee.

The New York parallel is instructive. New York Senate Bill S8921A, which would have retroactively decoupled New York from Section 1202 back to January 1, 2025, was withdrawn in March 2026 after pushback from the tech community. It was not defeated. The New York QSBS guide covers that situation in detail. Washington and New York are now both in a similar posture: conforming states where the conformity faces documented legislative pressure.

The new Millionaires' Income Tax and QSBS (effective 2028)

On March 30, 2026, Governor Bob Ferguson signed ESSB 6346, imposing a 9.9% income tax on household income exceeding $1 million per year, effective January 1, 2028.⁴ The Millionaires' Tax is a separate statute from the capital gains excise tax — it applies to income broadly, not just capital gains.

The QSBS interaction with the 2028 income tax is not yet settled. If the income tax statute, like the capital gains excise tax, uses federal taxable income as its starting point, then Section 1202-excluded gains would again be outside the state tax base. But the statute takes effect in 2028, and guidance from the Washington Department of Revenue on the income base and exclusions has not been finalized. Several legal challenges to the income tax are already underway, arguing that the Washington State Constitution effectively prohibits a personal income tax.

For most pre-2028 exits, the relevant analysis is the capital gains excise tax — where the conformity is clear and the stakes from SB 6229/HB 2292 are well-defined.

State comparison: Washington vs. California vs. New York

Planning priorities for Washington founders

1. Qualify rigorously — a failed exclusion is especially costly in Washington

A QSBS exclusion that fails at the federal level leaves the full gain exposed to the 9.9% Washington capital gains rate on any amount above $1 million. On a $15 million exit that fails qualification, the Washington state tax alone approaches $1.4 million, on top of the federal LTCG and NIIT. The payoff from getting qualification right is large enough that the documentation review and professional analysis of the eight Section 1202 tests is worth doing before a transaction closes — not after. See the QSBS qualification requirements guide for the full checklist, and the excluded industries guide for the §1202(e)(3) analysis relevant to Seattle-area software, biotech, and fintech companies.

2. Treat legislative risk as a planning variable, not just background noise

Charitable strategies and gifting to non-Washington residents can reduce the Washington state tax exposure that would result if a future legislative session adds QSBS gains back to the capital gains tax base. A DAF contribution of pre-transaction QSBS shares eliminates the gain from both federal and state tax entirely — the DAF is not a taxpayer. Gifting to a family member in a state that already has no income tax (Florida, Texas, Nevada) eliminates the state tax for those shares regardless of what Washington does next. These strategies require execution before a definitive purchase agreement or term sheet is signed. See the gifting and stacking guide and the charitable planning guide for timing rules and mechanics.

3. Model the 2028 income tax window if your exit is in the 2027–2028 range

The Millionaires' Income Tax (ESSB 6346) takes effect January 1, 2028. The interaction with QSBS-excluded gains is unresolved. Founders with optionality on a transaction timeline should model whether pulling a sale into 2027 — or structuring earnouts to land before 2028 — avoids meaningful exposure. This is a planning variable, not a panic signal; legal challenges may also resolve the income tax before it ever takes effect. The analysis requires current information from a Washington tax specialist.

4. Document the holding period and issuance facts with particular care

Washington's conformity depends on the federal exclusion working. If the IRS audits the Section 1202 exclusion — because the documentation is incomplete, the gross assets test failed at issuance, or the holding period clock was wrong — Washington will reassess as well. The 83(b) election proof, subscription agreement, QSBS attestation letter, and company gross assets confirmation at issuance are worth collecting and retaining in a format that will survive due diligence. See the QSBS documentation guide for what to preserve and how to reconstruct missing records.

5. Plan the post-exit portfolio for Washington's ongoing tax environment

After a successful QSBS exit, the proceeds go to work in a state that taxes future capital gains as ordinary excise income, with a 9.9% top rate on gains above $1 million. Post-exit portfolio design for Washington founders should account for this: direct indexing (systematic tax-loss harvesting against the 9.9% state rate), municipal bonds (interest is not capital gain and not subject to the WA excise tax), and charitable vehicles that absorb appreciated holdings before gains are recognized. The post-exit investing guide covers the framework.

What a QSBS advisor does for a Washington founder

Washington's current conformity is good news — but it is contingent, documented, and facing active political pressure. The combination of legislative risk, the new 9.9% CG rate tier, and the incoming 2028 income tax means that Washington QSBS planning requires current-year analysis, not just a general understanding of Section 1202.

• Model the complete state tax stack. Federal exclusion, Washington capital gains tax (current 9.9% regime), and the 2028 income tax overlay interact in ways that depend on the specific transaction structure, timing, and proceeds. An advisor builds the full picture before the transaction closes — not after.
• Assess and hedge legislative risk. A DAF, CRT, or gifting strategy executed before a letter of intent does not require a prediction about what the 2027 legislature will do. It reduces the maximum exposure to a legislative reversal while preserving the upside if conformity continues. The timing window for these strategies is the pre-LOI period — typically a few weeks or months before a transaction becomes definitive.
• Review QSBS qualification before any WA state risk matters. The Section 1202 exclusion does all the work at both the federal and state levels. A specialist advisor — one who has reviewed the eight qualification tests, the company's cap table history, and the issuance documentation — is the prerequisite for relying on the exclusion to begin with. See How to Choose a QSBS Advisor for the questions that distinguish real QSBS expertise.
• Coordinate with a Washington tax attorney on the 2028 income tax. The income tax is in litigation and in flux. A qualified advisor will have a current read on the DOR's administrative guidance, the legal challenges, and the practical implications for founders with pending transactions.

See also the state conformity guide for how Washington compares to Pennsylvania, Alabama, Mississippi, and other non-conforming states, and the New York QSBS guide for the parallel legislative-risk situation in the other major startup hub with conformity under pressure.

Talk to a QSBS advisor about your Washington situation

Washington conformity is a significant advantage over California — but it is statutory, not constitutional, and it survived the 2026 session by not advancing out of committee, not by a floor vote. The right time to model the exposure and execute any hedging strategies is before a transaction closes, not after the bills are filed.

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