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King County Property Tax Due Date

Washington

(206) 263-2890

2026 Property Tax Due Dates

Official Source
Installment 1

April 30

First half

Installment 2

October 31

Second half

Pay Taxes Online →
Penalty: 3% June 1, +8% December 1Grace period: None

Payment Methods

Online, Mail, In-Person

King County Treasurer

Treasurer

King County Treasury

Office Address

201 S. Jackson St., Suite 710
Seattle, WA 98104

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Office Hours

Mon-Fri 8:30am - 4:30pm

How to Pay

Online

Pay using credit card or e-check

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By Mail

Mail check payable to King County Treasurer

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In Person

Visit the Treasurer's office — 201 S. Jackson St., Suite 710, Seattle WA 98104, Mon-Fri 8:30am - 4:30pm

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About King County

King County is a county located in the U.S. state of Washington. The population was 2,269,675 in the 2020 census, making it the most populous county in Washington, and the 12th-most populous in the United States. The county seat is Seattle, also the state's most populous city.

Source: Wikipedia — content available under CC BY-SA 4.0

Get Deadline Reminders

We'll email you 20,160 minutes before your property taxes are due.

Due dates shown are for reference only. Contact your county treasurer's office to confirm official deadlines before making payments.