King County WA Property Tax: Search eReal, Pay Online, Check Due Dates & Appeal Value
Need to pay a King County property tax bill, find a parcel number, use eReal Property Search, check the April 30 or October 31 deadline, understand online payment fees, or appeal a valuation notice? This guide puts the official King County workflow in one place: Assessor for values and tax relief, Treasury for payment, Board of Appeals for valuation appeals, and Tax Advisor for independent help.
What King County property owners usually need first
Choose the path that matches your problem. King County property tax involves different offices, and using the wrong one wastes time.
Fast action board
- 1Need to pay or check balance? Use the King County property tax payment system. You need the real property tax account or parcel number.
- 2Do not know parcel/account number? Use eReal Property Search by address, then copy the parcel or tax account number into the payment portal.
- 3Mortgage company pays? King County says it is still the taxpayer’s responsibility to make sure taxes are paid on time.
- 4Assessment seems wrong? Review eReal property characteristics first. If data is wrong, contact the Assessor before filing an appeal.
- 5Need senior/disabled relief? King County lists online exemption applications for seniors, disabled persons and qualifying disabled veterans.
Official pages to keep open
Assessor values
Valuations, property details, relief programs and value notices.
Levies are applied
State, county, city, school and special district levies create the bill.
Treasury bills
Treasury collects real and personal property taxes.
You pay or appeal
Pay by due dates; appeal value by the appeal deadline.
How to look up King County property tax by address or parcel
King County payment lookup works best when you already have the account or parcel number. eReal Property Search is the tool to find it if you only know the address.
| Need | Official Tool | What It Helps You Find |
|---|---|---|
| Address to parcel/account | eReal Property Search | Parcel number, account information, valuation, property characteristics, levy rates and sale history. |
| Pay tax bill | King County Property Tax Payment | Current half-year payments, full-year payment, delinquent years and statement options. |
| Personal property / mobile home account | Treasury or Assessor phone support | Personal property account number when it is not searchable like real property. |
| Assessment appeal evidence | eReal + Assessor records | Property facts, sale history, value history and levy information. |
1Open eReal Property Search if you only know the addressFind the parcel/account number first.▾
Open King County eReal Property Search. Search by property address and copy the parcel or tax account number. Do not include dashes when entering it in the payment system.
2Open the property tax payment accountUse this for balance, statement and payment.▾
Open King County Property Taxes. Enter the account or parcel number and review the taxpayer name, mailing address, tax statement and payment boxes before paying.
3Need a tax statement?Expand the tax statement section after searching.▾
King County’s FAQ says that after entering the tax account number, scroll to the Tax Statement section, expand the screen with the plus symbol, and use the Request Tax Statement button if available.
How to pay King County property taxes
King County supports online, mail and in-person/drop-box options. Pick the method based on deadline, fee and receipt needs.
| Payment Method | Official Detail | Best For |
|---|---|---|
| Online credit/debit card | Beginning Jan. 1, 2026, debit and credit card payments are subject to a 2.35% service fee with a $2.00 minimum. | Fast payment when fee is acceptable. |
| Online eCheck | eCheck payment fee is $0.55; it deducts from a checking account. | Lower-fee online payment. |
| Pay by mail | Mail to King County Treasury, 201 S. Jackson St., Suite 710, Seattle, WA 98104. Include tax account number. | Check, cashier’s check or money order postmarked by due date. |
| In person / drop box | King Street Center, 201 S. Jackson St., Seattle. Drop box is available Monday–Friday, 8:30 a.m.–4:30 p.m. | Local payment or account help during business hours. |
| Payment plan | Contact PaymentPlans@kingcounty.gov or 206-263-2649 for possible six- or 12-month options. | Selected delinquent/homeowner situations, not a quick online partial payment. |
1Verify parcel/account before payingWrong account payments are painful to fix.▾
Match the tax account or parcel number, property address, taxpayer name, tax year, half-year payment boxes, full-year total and delinquent years before submitting.
2Choose half-year or full-year correctlyReal property can pay either or both current half-year boxes.▾
For real property, King County says you can pay half-year taxes, full-year taxes and delinquent taxes online. To pay the full year, check both current half-year boxes.
3Save confirmation immediatelyEspecially if deadline is near.▾
Save the confirmation email, transaction time, payment amount, parcel/account number and payment method. King County says the online payment is effective as of the date and time in the confirmation email.
King County property tax deadlines, late charges and foreclosure risk
These are the dates most homeowners search for. Put reminders in your calendar even if you use escrow.
| Date / Event | Official Rule | What To Do |
|---|---|---|
| April 30 | First half property taxes due. If taxes are under $50, full payment is due. | Pay or postmark by this date; check both account and escrow status. |
| May 1 | Monthly late charges begin after the first-half deadline. | Call Treasury if payoff is unclear or if foreclosure costs may apply. |
| July 1 | County Board of Equalization appeals are generally due by July 1 or within 60 days after the value notice. | File appeal on time; do not wait for tax bill frustration later. |
| September 1 | Limited-income deferral applications are due each year. | Review eligibility early; first half must be paid before applying for 2nd installment deferral. |
| October 31 | Second half taxes due. | Pay or postmark by this date to avoid November 1 delinquency. |
| Tax foreclosure | Real property with at least one year’s tax that is three years past due is subject to foreclosure. | Call 206-263-2649 before guessing payoff on foreclosure accounts. |
Assessed value, property characteristics and why taxes increase
King County explains that voter-approved measures and taxing district levies can drive tax increases; a higher value alone does not always explain the full tax bill.
Assessor role
The Assessor appraises residential and commercial property, maintains property data and administers tax relief programs.
eReal shows details
Use eReal to review valuations, property characteristics, levy rates and sale history.
County share
King County states it receives about 20% of property taxes to fund services such as roads, criminal justice and public health.
2026 context
King County’s 2026 property tax overview lists total countywide property taxes at about $8.4 billion, up roughly 10% from the prior year.
Levy measures matter
School, parks, fire, hospital, EMS and voter-approved measures can affect the bill depending on location.
Tax Advisor
The independent Tax Advisor helps taxpayers navigate assessments, exemptions, appeals, property taxes and records.
How to appeal a King County property valuation
Appealing is about the assessed value, not simply that the tax bill is too high. Evidence matters.
1Review your property facts in eReal firstA data error may be fixable without a full appeal.▾
King County advises reviewing property characteristics on eReal Property. If the data is wrong, contact the Assessor’s Office at 206-296-7300 or Assessor.Info@KingCounty.gov.
2File by the correct deadlineJuly 1 or 60 days after your value notice.▾
King County says the petition must generally be postmarked or filed online by July 1 of the assessment year or no later than 60 days after the value-change notice.
3Bring evidence, not just opinionComparable sales and property errors matter most.▾
Use comparable sales, recent appraisal, condition issues, square footage or property-characteristic errors, photos and market evidence. King County notes that proper evidence is essential.
4Pay taxes by deadline even if appeal is pendingAvoid interest and penalties.▾
King County says if taxes are due before your hearing or decision, pay them by the deadline. If value is reduced after payment, the Treasurer may issue a revised statement or refund.
Board of Appeals
Email: BOE@kingcounty.gov
Phone: 206-477-3400
Tax Advisor
Email: taxadvisor@kingcounty.gov
Phone: 206-477-1060
Assessor
Email: Assessor.Info@KingCounty.gov
Phone: 206-296-7300
King County senior, disabled, veteran and limited-income tax relief
Tax relief can matter more than appeal for eligible homeowners. King County strongly encourages online applications for faster processing.
Senior / disabled exemption
Basic qualifications listed by King County: own and live in the home, be at least 61 or disabled by Dec. 31 of the preceding year, and meet income rules.
Current income threshold
For 2024, 2025 and 2026 property-tax reductions, King County’s portal lists household income of $84,000 or less after qualified deductions.
Disabled veteran route
The Assessor page lists relief links for disabled veterans and disabled persons who meet program requirements.
Limited-income deferral
King County lists a limited-income deferral for qualifying homeowners with $57,000 or less previous-year income, ownership/occupancy rules and equity requirements.
Deferral is not free money
The limited-income deferral is not an exemption or grant. Deferred taxes and interest become a lien until repaid.
Destroyed property relief
Flood, fire, earthquake or other destroyed-property situations may qualify for separate relief depending on timing and facts.
Can King County property taxes be put on a payment plan?
King County lists payment-plan information for homeowners, but it is not the same as making small partial payments directly to Treasury.
Who to contact
Email PaymentPlans@kingcounty.gov or call 206-263-2649.
Information to provide
Send contact information, tax account number, tax year needing the plan and whether you want six or 12 months.
Account still shows unpaid
King County says the account appears unpaid until the plan is completed and funds are sent to Treasury.
Mortgage reminder
If you have a mortgage, King County says to contact your lender and tell them about the payment-plan agreement.
King County property tax contacts, addresses and map
Use Treasury for payment. Use Assessor for value, property data and tax relief. Use BOE for appeals. Use Tax Advisor for independent appeal/property-tax guidance.
Treasury Operations
King Street Center
201 S. Jackson St., Suite 710
Seattle, WA 98104
Phone: 206-263-2890
Email: PropertyTax.CustomerService@kingcounty.gov
Assessor
King Street Center Customer Service Center
201 S. Jackson St., 2nd Floor
Seattle, WA 98104
Phone: 206-296-7300
Email: Assessor.info@kingcounty.gov
Tax Advisor
810 3rd Ave, Suite 705
Seattle, WA 98104
Phone: 206-477-1060
Email: taxadvisor@kingcounty.gov
Foreclosure / payment plan
Foreclosure and payment-plan help: 206-263-2649
Personal property/mobile homes: 206-263-2844
Map to King Street Center
King County Treasury and Assessor customer service are both listed at King Street Center, but on different floors/suites. Confirm the exact department before visiting.
Official King County property tax links
Use these links for final actions only: paying, looking up parcel records, applying for relief, filing appeals or contacting the right office.
King County Washington property tax FAQs
Short answers for homeowners, investors, seniors, escrow users and anyone trying to pay or appeal property taxes in King County.
QHow do I look up King County property taxes?▾
Use eReal Property Search to find your parcel or tax account number by address, then enter that number in King County’s property tax payment system.
QWhen are King County property taxes due?▾
First half is due April 30 and second half is due October 31. If total taxes are under $50, the full amount is due April 30.
QWhat happens after April 30?▾
If first-half taxes are not paid or postmarked by April 30, the full-year tax becomes delinquent on May 1 and monthly late charges begin.
QWhat are online payment fees?▾
Beginning Jan. 1, 2026, debit and credit card payments have a 2.35% service fee with a $2.00 minimum. eCheck payments have a $0.55 service fee.
QCan I pay the whole year online?▾
For real property, yes. King County says to check both boxes for the two current half-year payments to pay the full year.
QWhat if my mortgage company pays?▾
King County says it remains the taxpayer’s responsibility to make sure taxes are paid on time. Verify the account before the due date.
QWho handles assessed value?▾
The King County Assessor handles value, property characteristics, relief programs and valuation notices. Treasury handles billing and collection.
QHow long do I have to appeal?▾
King County says appeals are generally due by July 1 of the assessment year or within 60 days after the value-change notice.
QCan seniors get a King County property tax reduction?▾
Yes, if eligible. King County’s portal lists basic requirements including ownership/occupancy, age 61 or disability by Dec. 31 of the prior year, and the current income limit.
QIs this an official King County website?▾
No. PropertyTaxUSA.org is independent. Verify tax balances, deadlines, payment fees, relief eligibility and appeal status with official King County offices.
Bottom line
For King County property tax, think: eReal finds the parcel, Treasury collects the bill, Assessor handles value and tax relief, and the Board of Appeals handles valuation appeals. Pay by April 30 and October 31, save every confirmation, and do not wait until a bill is late to check escrow or appeal options.
Independent guide notice: This page is informational only and is not King County, the Treasury, the Assessor, the Board of Appeals and Equalization, Washington Department of Revenue, a payment processor or legal advice.