Return filing and extensions

Individuals must file their capital gains tax return by the same day as the individual's federal income tax return is due.

To receive an extension for filing your Washington Capital Gain return, you must request an extension for your capital gains tax return by submitting a request electronically through My DOR on or before April 15. To qualify for the extension you must have received a filing extension for your federal income tax return. A filing extension does not extend the due date for submitting a payment.

All taxpayers must electronically file their capital gains excise tax returns along with a copy of their federal tax return and all required documentation. The department may waive the electronic filing requirement for good cause, however, the waiver must be granted before you file your return. To file electronically go to My DOR or select tax preparation software .

Penalties will apply to late returns.

If an extension is requested or a payment is made, you must file a return with the department regardless of any tax being due.