Washington Department of Revenue Filing Deadlines Updated
The Washington Department of Revenue has released updated filing deadlines for the 2026 tax year, providing businesses with clear timelines for excise tax returns and payments. The guidance outlines due dates for monthly, quarterly, and annual filers, as well as rules for electronic payments and late penalties.
The Washington Department of Revenue published its 2026 excise tax filing schedule through official guidance on dor.wa.gov. The schedule applies to all businesses required to file Combined Excise Tax Returns and reflects standard reporting frequencies assigned by the department.
According to the Department of Revenue, filing deadlines are based on whether a taxpayer files monthly, quarterly, or annually. The department notes that taxpayers are responsible for meeting deadlines even if they do not receive a reminder notice. All official due dates are maintained through department publications and online resources.
The updated schedule confirms that filing deadlines may shift when due dates fall on weekends or legal holidays, extending automatically to the next business day.
Businesses classified as monthly filers must submit excise tax returns by the 25th day of the month following the reporting period. For example, returns covering January 2026 activity were due February 25, 2026, consistent with the department’s standard timeline.
When the 25th falls on a weekend or state-recognized holiday, the Washington Department of Revenue extends the deadline to the next business day. This adjustment applies to all monthly filing periods throughout the year.
The Department of Revenue applies a tiered penalty structure for late filings. A 9 percent penalty is assessed beginning the day after the due date. The penalty increases to 19 percent after approximately 30 days and rises to 29 percent after approximately 60 days. Interest may accrue in addition to penalties.
Quarterly filers must submit excise tax returns by the last day of the month following each calendar quarter. For the 2026 tax year, first-quarter returns covering January through March are due April 30, 2026.
Second-quarter returns are due July 31, 2026; third-quarter returns are due October 31, 2026; and fourth-quarter returns are due January 31, 2027. The same penalty structure applies if returns or payments are filed late.
Annual filers reporting on a calendar-year basis must submit their 2026 Combined Excise Tax Return by April 15, 2027. The Washington Department of Revenue aligns this deadline with the federal individual income tax filing deadline, offering consistency for taxpayers managing both state and federal obligations.
Taxpayers using Electronic Funds Transfer debit or the My DOR system must complete payments by 11:59 p.m. Pacific Time on the filing date. In these cases, the department allows a one-day processing window, with the official payment due date falling the following day.
EFT credit users must ensure funds are deposited into the state’s account by 5:00 p.m. Pacific Time on the payment due date. The Department of Revenue notes that banks may impose earlier internal cutoff times, making it essential for taxpayers to coordinate payments in advance.
The Washington Department of Revenue advises businesses to review their assigned filing frequency and confirm payment methods before each deadline. Missing a filing or payment deadline can quickly lead to penalties and interest, increasing overall tax liability.
Businesses experiencing changes in revenue should also confirm whether their filing frequency remains accurate for 2026. The department encourages taxpayers to use My DOR accounts to track due dates, confirm submissions, and access official notices. For authoritative and up-to-date information, taxpayers should rely exclusively on official Department of Revenue guidance published on dor.wa.gov.
By William Mc Lee, Editor-in-Chief & Tax Expert—Get Tax Relief Now
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