Washington Capital Gains Tax Returns Due Date Moved to May 1, 2026

WA DOR News Releases

Published March 25th, 2026

Detected March 26th, 2026

Summary

The Washington State Department of Revenue has extended the due date for Tax Year 2025 Capital Gains tax returns and payments from April 15, 2026, to May 1, 2026. This extension aligns with IRS tax relief for Washington residents affected by severe storms and flooding.

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What changed

The Washington State Department of Revenue (DOR) has announced that the due date for Tax Year 2025 Capital Gains tax returns and payments has been moved from April 15, 2026, to May 1, 2026. This change is made for convenience and aligns with the IRS's extension of tax filing and payment deadlines to May 1, 2026, for Washington state residents and businesses impacted by severe storms and flooding that began in December 2025.

While the payment deadline is now May 1, 2026, individuals seeking a filing extension must request it by May 1, 2026, and must also have an extended federal income tax return. The extended filing deadline for these individuals will be October 15, 2026. It is crucial to note that a filing extension does not extend the payment deadline; payments remain due by May 1, 2026.

What to do next

File Tax Year 2025 Capital Gains tax returns by May 1, 2026.
Make Tax Year 2025 Capital Gains tax payments by May 1, 2026.
Request filing extension by May 1, 2026, if federal extension is also obtained, for an extended filing deadline of October 15, 2026.

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Capital Gains Excise Tax Returns Due Date Moved To May 1, 2026

Capital Gains Excise Tax returns due date moved to May 1, 2026

OLYMPIA, Wash. – March 25, 2026 – Tax Year 2025 Capital Gains tax returns and payments are due May 1, 2026.

The Internal Revenue Service (IRS) has extended tax filing and payment deadlines to May 1, 2026 for Washington state residents and businesses affected by severe storms and flooding that began Dec. 9, 2025. For convenience, the April 15, 2026 due date for all Washington Capital Gains tax returns and payments has been extended to May 1, 2026 for the 2025 filing year only.

Filing extensions

Individuals must request an extension for their state capital gains return by May 1, 2026, and receive a filing extension for their federal income tax return to be entitled to a filing extension. The extended filing deadline is Oct. 15, 2026.

A filing extension does not extend the due date for paying the capital gains tax due. Payments are due May 1, 2026.

The Department of Revenue is Washington state’s primary tax agency, nationally recognized as a trusted leader in tax administration and customer service. Revenue administers nearly 60 categories of taxes that help fund vital public services. It also oversees programs that return money to the public, including the Working Families Tax Credit and Unclaimed Property.