QSBS and Washington's New Millionaire Tax

By Joe Wallin,

Published on Mar 15, 2026   —   1 min read

If you sold qualified small business stock and excluded the gain under IRC § 1202, you may be wondering whether Washington's new millionaire tax applies to that gain.

The short answer: it shouldn't.

Washington's tax starts with your federal adjusted gross income (AGI). Gains excluded under § 1202 never enter your federal AGI in the first place — they're excluded at the federal level before AGI is calculated. Because the WA tax uses federal AGI as its starting point, and there is no specific add-back provision for § 1202 gains, those excluded gains should not be subject to the Washington millionaire tax.

For a deeper dive into how Washington's new income tax works — including the rates, thresholds, and what counts toward the tax base — read our comprehensive guide: Washington's New Income Tax: What Founders, Investors, and High Earners Need to Know.

This post is for informational purposes only and does not constitute legal or tax advice. Consult a qualified tax professional for advice specific to your situation.

Share on Facebook Share on Linkedin Share on Twitter Send by email

Subscribe to the newsletter

Practical updates on QSBS, Washington taxes, equity compensation, and startup law — for founders, investors, and startup employees.

Subscribe