Washington State Opens Payment Site for Disputed Capital Gains Tax

Washington state launched an online registration and filing system for its new capital gains tax so taxpayers can make their first payments due April 18, the Department of Revenue said Monday.

The filing portal allows the department to begin collections while waiting for a state Supreme Court ruling on the constitutionality of the tax. Justices heard oral arguments in January in a challenge by farming and business groups arguing that it’s an improper income tax, not an excise tax.

• If the court finds the capital gains tax is unconstitutional, payments will be refunded promptly with interest, the department said.
• The ...