King County, WA Property Tax: Rates, Exemptions, and Appeals

Property tax rates in King County for 2025 run from roughly $6.18 to nearly $11.87 per $1,000 of assessed value, depending on which taxing districts overlap your property. A home assessed at $700,000 in Seattle, where consolidated rates sit around $9.19 to $11.27 per $1,000, would owe between about $6,400 and $7,900 for the year. There is no single countywide number because each parcel falls inside a unique combination of state, county, city, school, and special district levies.¹

2025 Rates by City

The King County Assessor publishes a consolidated levy rate for each “tax code area,” which bundles every overlapping jurisdiction into one number expressed in dollars per $1,000 of assessed value. For 2025, the lowest consolidated rate in the county is in Hunts Point at roughly $6.26 per $1,000. The highest sits in certain unincorporated Auburn school-district zones at about $11.86 per $1,000.¹

Representative 2025 ranges for major cities:

Seattle: $9.19 to $11.27 per $1,000
Bellevue: $7.33 to $8.80 per $1,000
Kent: $9.30 to $10.84 per $1,000
Renton: $9.23 to $10.02 per $1,000
Tukwila: $9.08 to $11.45 per $1,000

Even within one city, different neighborhoods can fall under different school districts, fire districts, or utility districts, which is why every city shows a range rather than a single figure. To pin down the exact rate for your address, look up your parcel on the King County Assessor’s website.¹

Why the Rate Changes Every Year

Washington uses a budget-based property tax system. Each taxing district first decides how much revenue it needs for the year. That total dollar amount is then divided by the combined assessed value of all taxable property in the district, and the result is the rate per $1,000.²

That formula has a counterintuitive result. When total assessed values across a district rise sharply, the rate per $1,000 drops, because the same revenue is being spread across a larger base. When values decline, the rate climbs. Your individual bill depends on how your property’s assessed value moves relative to every other property in the district. If your home gained 20% in value while the district average gained 10%, your share of the burden goes up even if the rate itself stayed flat.

How Assessed Value Sets Your Share

Washington law requires all property to be valued at 100% of its true and fair market value, meaning the price a willing buyer and willing seller would agree on in an open transaction.³ The King County Assessor sets that value for every parcel.

Appraisers physically inspect each property at least once every six years, checking square footage, construction quality, and condition.⁴ Between visits, the office updates values annually through statistical analysis of comparable sales. Your assessed value can change every year even when nobody has walked the property. That number does not determine the total taxes a district collects. It determines how much of that total you pay compared to every other owner.

The One Percent Cap and Voter Levies

State law limits how fast a district’s total regular levy collections can grow. Under the one percent levy limit, a district cannot raise its regular levy revenue by more than 1% over the prior year, plus revenue from new construction.² The cap applies to the district’s total, not to any individual bill, so your own tax can still climb faster than 1% when your assessed value outpaces the district average.

Voter-approved levies are the main way rates jump above that baseline. School districts regularly ask voters to approve construction bonds and operational levies. Cities and other districts sometimes pass “lid lifts” that allow the district to exceed the 1% growth limit for a single year or for up to six consecutive years.⁵ Those measures are the biggest reason a home in one neighborhood can carry a noticeably higher rate than a similar home a few miles away.

Exemptions That Can Lower Your Bill

Washington offers substantial property tax relief for qualifying homeowners. Under RCW 84.36.381, the program covers three groups:⁶

Seniors who were at least 61 years old by December 31 of the year they file
People retired from regular employment because of a disability
Disabled veterans with a combined service-connected rating of 40% or higher, or a total disability rating for a service-connected disability

The property must be your primary residence, and your total household income after qualified expense deductions must be $84,000 or less.⁷ The exemption is tiered, with larger reductions at lower income levels. Thresholds are tied to a percentage of King County median household income and adjust periodically.⁸

If you qualify but would rather keep the taxes on the books, Washington also runs a deferral program under RCW 84.38. Unpaid taxes accumulate as a lien against the property, accrue simple interest at 5%, and come due when you sell, move out, or pass away.⁹ It works for owners who are property-rich and cash-poor and want to stay put.

Appealing Your Assessed Value

Because your bill is driven by assessed value, an incorrect assessment is often the fastest way to reduce it. Petitions to the King County Board of Equalization must be postmarked, hand-delivered, or filed online by the later of July 1 of the assessment year or 60 days from the mailing date printed on your valuation notice.¹⁰

A successful appeal requires evidence that the Assessor’s number does not match true market value. Recent sale prices of comparable homes in your neighborhood carry the most weight. The Board will not consider arguments about how much your taxes went up, how your percentage increase compares to a neighbor’s, or personal financial hardship. The only question is whether the market value is right.¹⁰

Before filing formally, call the Assessor’s office. Errors in property characteristics, like an incorrect square footage, a phantom bedroom, or a basement listed as finished when it is not, can sometimes be corrected without a hearing.

Payment Deadlines and Late Interest

King County property taxes are paid in two installments. For the 2026 tax year, the first half is due April 30 and the second half is due October 31. If your total bill is under $50, the full amount is due April 30. When a due date falls on a weekend or legal holiday, it shifts to the next business day.¹¹

Late consequences depend on the type of property:

Residential property with four or fewer units: interest accrues at 9% per year on the delinquent amount, calculated monthly, with no flat penalties.¹²
All other property, including commercial, multifamily with five or more units, and personal property: interest at 12% per year, plus a 3% penalty on June 1 and an additional 8% penalty on December 1 of the year the tax was due.¹²

Interest runs from the original due date, so a few months of delay adds up. If taxes stay unpaid for three years, the county can begin foreclosure.

1
King County. 2025 King County Codes and Levies
2
Washington Department of Revenue. Property Tax – How the 1% Property Tax Levy Limit Works
3
Washington State Legislature. RCW 84.40.030 – Manner of Assessment of Real and Personal Property
4
King County, Washington. Property Field Inspection Frequently Asked Questions
5
Cornell Law Institute. WAC 458-19-045 – Levy Limit Removal of Limit (Lid Lift)
6
Washington State Legislature. RCW 84.36.381 – Exemptions – Qualifications
7
King County, Washington. Senior Exemption Portal
8
Washington State Legislature. RCW 84.36.383
9
Washington Department of Revenue. Property Tax Exemptions and Deferrals
10
King County, Washington. How to Appeal a Property Tax Assessment
11
Washington Department of Revenue. 2026 Property Tax Calendar Due Dates
12
Washington State Legislature. RCW 84.56.020