Second half of 2026 property taxes due November 2

King County property owners who pay their property taxes themselves, rather than through a mortgage lender, have until Monday, November 2 to pay the second half of their 2026 bill. 

After that date, late charges will be added to the tax bill. Normally, the second half would be due on the statutory deadline of October 31, but because that date falls on a Saturday this year, taxpayers have until the next regular business day.

To make the payment process easier, King County provides several ways for property owners to pay their taxes quickly and conveniently. Payments can be made:

• Online using King County's secure online eCommerce system at kingcounty.gov/PropertyTax. Taxpayers may pay with a credit card, debit card, or an electronic check. A service fee applies to this option. While on the website, taxpayers can also sign up to receive text or email reminders about tax due dates.

• By mail if postmarked no later than November 2, 2026. Payments should be addressed to King County Treasury, 201 S. Jackson St., Suite 710, Seattle, WA 98104. Please include the property tax account number on the check or money order. Taxpayers do not need to include a tax statement with the payment as long as the property tax account number is on the check or money order and payment is for the exact amount due. Cash should not be sent through the mail.

• In person at the King County Customer Service Center, 201 S. Jackson St., second floor, in Seattle's Pioneer Square neighborhood. CSC hours are 8:30 a.m. to 4:30 p.m. weekdays. In-person payments can be made by credit card, debit card, check or money order, or cash. A service fee applies to card payments.

• By secure drop box inside King Street Center at 201 S. Jackson St. The drop box is available from 8:30 a.m. to 4:30 p.m. weekdays. Drop box payments should be made by check or money order. Cash should not be left in the drop box.

To help taxpayers impacted by economic hardship, King County offers a payment plan program for delinquent real property accounts, including homes, commercial businesses, land, and mobile homes. Statutory late charges are calculated into these payment plans. 

To participate, property owners must sign an agreement with King County Treasury. If participating owners also have a mortgage, they need to notify their lender about the payment plan. The program is administered through a third-party vendor and monthly payments are credited to the property tax account once the terms of the payment plan are met. For more information on the payment plan program, please visit kingcounty.gov/PropertyTax/PaymentPlans.

For questions about the tax bill or other tax payment information, visit kingcounty.gov/PropertyTax, contact King County Treasury Operations at propertytax.customerservice@kingcounty.gov or call 206-263-2890.

Information on exemption and deferral programs for seniors, people with disabilities, or other qualifying conditions can be obtained from the King County Assessor's Office at TaxRelief.kingcounty.gov, by emailing exemptions.assessments@kingcounty.gov, or calling 206-296-3920.