King County, WA property tax deadlines
6 coming property tax dates for King County, Washington. Each one links to its official source and shows the day LevyDay last checked it.
| Next dates | Bills due | Last day without penalty | Appeal by | Exemption filing |
|---|---|---|---|---|
| King | Not on file | Nov 2, 2026kingcounty.govOct 21 | Jul 1, 2027kingcounty.govOct 21 | Dec 31, 2026app.leg.wa.govOct 21 |
Deadlines in date order
| Date and source | Deadline |
|---|---|
| April 30 every yearapp.leg.wa.govOct 21 | Last day without penalty First half due (or all of it, if under $50) It's late after April 30. If the year's tax is under $50, pay it all by April 30. |
| July 1 every yearkingcounty.govOct 21 | Appeal deadline Appeal your value File online or postmark it by July 1 of the assessment year, or within 60 days of the mailing date on your value notice. |
| October 31 every yearkingcounty.govOct 21 | Other Weekend and holiday due dates move The halves are due April 30 and October 31. If either lands on a weekend or county holiday, pay the next working day. |
| October 31 every yearapp.leg.wa.govOct 21 | Last day without penalty Second half due It's late after October 31. |
| November 2, 2026 2026 onlykingcounty.govOct 21 | Last day without penalty 2026 second half due (Oct 31 is a Saturday) |
| December 31 every yearapp.leg.wa.govOct 21 | Exemption filing Renew your senior or disabled exemption Only in a year the assessor tells you to renew, which is at least every six years. A first claim can be filed any time in the year, for taxes due the next year. |
Appealing your assessed value
Appeal by Jul 1, 2027 in 251 dayskingcounty.govOct 21
If you think the county valued your home too high, you can appeal. Filing with the county is free and you can do it yourself.
Get help filing an appeal
After you send your details, we look for an independent appeal firm or attorney to take your case. We'll be in touch once one has agreed. Firms usually charge a share of what you save, and the one that takes it may pay LevyDay a referral fee.
LevyDay doesn't file appeals or give legal or tax advice. We only pass your details on. The independent firm or attorney that takes your case does the work and sets its own fee.
Get help filing an appealGood to know in Washington
- Paying late: Delinquent tax on residential property with four or fewer units, including manufactured homes, carries interest of nine percent a year. Other property is charged twelve percent. More app.leg.wa.govOct 21
- Appealing your value: You appeal your assessed value by filing a petition with the county board of equalization, on a form prescribed or approved by the Department of Revenue. More app.leg.wa.govOct 21
- Homestead exemption: If you meet criteria such as age and income, you may be eligible for the exemption for senior citizens and people with disabilities. Apply through your county assessor. More dor.wa.govOct 21
Free reminders from the county
- King County sends an email or text message reminder about 30 days before the April 30 and October 31 property tax deadlines if you sign up on its property tax page. Sign up with the county
Official offices
- King County Treasury Operations - Property Tax
- King County Board of Equalization (Property Tax Advisor)
Places in King County
Among them: Algona, Ames Lake, Auburn, Baring, Beaux Arts Village, Bellevue, Black Diamond, Bothell, Boulevard Park, Bryn Mawr-Skyway, Burien, Carnation, Clyde Hill, Cottage Lake, Covington, Des Moines, Duvall, East Renton Highlands, Enumclaw, Fairwood, Fall City, Federal Way, Hobart, Hunts Point, and 39 more. Every place in the county gets the dates above.
Nearby in the Washington list
FranklinGarfieldGrantGrays HarborIslandJeffersonKitsapKittitasKlickitatLewisLincolnMason