King County Washington Property Tax Guide: Pay, Search, Due Dates & Exemptions
King County property tax has two main offices. The Department of Assessments handles property value, characteristics, valuation notices and many tax-relief programs. King County Treasury Operations handles tax bills, payments, receipts, payment reminders and delinquent tax collection.
Use this image-free guide to pay safely, search by parcel or tax account, understand the April 30 and October 31 due dates, review senior or disabled tax relief, prepare a valuation appeal, and avoid common mistakes with escrow, late payments and personal property accounts.
Quick Answer: Where to Start for King County Property Tax
For a bill, balance, receipt, tax statement, payment plan, late charge or foreclosure question, start with King County Treasury Operations. Treasury is the payment and collection side of the property tax process.
For value, property characteristics, valuation notice, exemptions, deferrals, destroyed-property relief or assessment appeal questions, start with King County Department of Assessments or the Board of Appeals and Equalization.
Fast Route: Which King County Office Do You Need?
Use this table before clicking an official link. It separates payment tasks from assessment tasks so you do not waste time on the wrong office page.
| Your Task | Start With | Why | Best Next Step |
|---|---|---|---|
| Pay current property tax | King County Treasury Operations | Treasury collects real and personal property tax bills. | Use the official King County payment portal. |
| Find tax account number | eReal Property or tax statement | The payment portal needs a tax account or parcel number. | Search eReal by address or parcel, then open the payment portal. |
| Value looks too high | Department of Assessments | Assessments controls valuation and property characteristics. | Review eReal, contact Assessor, then appeal if needed. |
| Need senior or disabled exemption | Assessor Tax Relief | Exemptions and deferrals are handled through Assessments. | Use the online senior exemption portal or paper forms. |
| Filed appeal or missed appeal deadline | Board of Appeals and Equalization | The Board handles property valuation petitions. | Check July 1 or 60-day deadline rules. |
King County Property Tax Due Dates and Key Deadlines
King County property taxes are generally paid in two installments. First-half taxes are due April 30, and second-half taxes are due October 31. If a due date falls on a weekend or King County holiday, the due date moves to the next business day.
Always verify the current tax year and the exact date shown in the King County payment portal or on the county statement. Mail payments must be postmarked on time.
| Date or Window | What It Means | What to Do |
|---|---|---|
| April 30 | First-half real property taxes are due. If the total tax is less than $50, the full payment is due. | Pay online, by mail, or in person before the deadline. |
| April 30 | Personal property listing forms are also due for applicable business/personal property accounts. | Use eListing or King County personal property instructions. |
| May 1 | Monthly late charges begin after the first-half due date if taxes are not paid on time. | Check the exact balance in the payment portal before paying late. |
| July 1 or 60 days after notice | Common valuation appeal deadline route for the Board of Equalization. | File online or by mail before the later official deadline for your notice. |
| September 1 | Application deadline for limited-income deferrals listed in King County’s 2026 calendar. | Review deferral eligibility early with the Assessor’s office. |
| October 31 | Second-half property taxes are due. | Confirm mortgage escrow or pay directly before late charges begin. |
| November 1 | Monthly late charges begin for unpaid second-half taxes. | Use the payment portal for real property balance or call for personal property amounts. |
Deadline warning: Payment reminders are helpful, but King County says owners are still responsible for paying on time even if a reminder does not arrive.
How to Pay King County Washington Property Tax Online
King County’s official payment portal lets taxpayers pay real property and personal property tax bills. You need your tax account number or parcel number to look up the account.
Beginning January 1, 2026, King County’s payment page states debit and credit card payments have a 2.35% service fee with a $2.00 minimum. The fee is charged by the payment processor, not retained by King County.
- Open the official King County Property Taxes payment portal.
- Enter the tax account or parcel number.
- Confirm taxpayer name, mailing address, tax year and balance.
- Choose online payment, mail payment or in-person payment as appropriate.
- Review service fees before submitting card or electronic payment.
- Save the confirmation number, receipt, bank record and tax year details.
Payment safety tip: Use KingCounty.gov or Payment.KingCounty.gov. Avoid search ads, look-alike portals, and third-party pages that do not clearly show the official King County payment system.
How to Get a King County Tax Statement or Receipt
If you know your tax account number, the King County payment system can show account information and tax statement options. If you do not know the number, use eReal Property first to search by address or parcel.
The account record may change if payments are pending, recently posted, or corrected. Always save the receipt after payment and re-check the account if you need proof for escrow, closing or records.
How to Search King County Property Tax Records
King County has more than one search tool. eReal Property is the best starting point for valuations, property characteristics, levy rates and sale history. The payment portal is best for bills, balances and receipts.
For location-based research, King County also has map and GIS tools. Use those for parcel context, mapping layers, property research and neighborhood information.
| Search Goal | Official Tool | Search By | What You May Find |
|---|---|---|---|
| Property value and characteristics | eReal Property | Parcel number, tax account, address, condo/apartment complex | Valuation, building details, land data, levy rates and sale history. |
| Tax bill and payment status | King County payment portal | Tax account or parcel number | Balance, tax statement, payment options and receipt status. |
| Comparable sales | eSales | Residential or commercial property type | Sales data to help understand or appeal value. |
| Map and GIS view | Parcel viewer, eMap or iMap | Parcel number or map location | Spatial layers, parcel location and surrounding property context. |
- Open King County’s property information lookup page.
- Use eReal Property for valuation and property characteristics.
- Copy the tax account or parcel number.
- Use that number in the payment portal for tax statements and payment records.
- Save the account details before filing an appeal or payment dispute.
King County Property Assessment: Value Notice vs Tax Bill
The Department of Assessments values property and sends valuation notices. That value helps determine the taxes payable the following year, after levies and rates are applied.
A valuation notice is not the same as a tax bill. The notice is the moment to check property characteristics and appeal value. The tax bill is the collection document used for payment.
| Term | Plain Meaning | Why It Matters |
|---|---|---|
| Valuation notice | Notice from the Assessor showing the value placed on the property. | Starts the appeal review period for many owners. |
| Assessment year | The year the value is assessed. | It generally affects taxes payable in the following tax year. |
| Tax account number | Number used to identify the tax account for payment and statement lookup. | Needed for the payment portal and tax statement requests. |
| Levy rate | Rate applied by taxing districts to raise approved tax amounts. | Your bill depends on both value and local levies. |
| Tax statement | Bill showing amount due and payment deadlines. | Treasury Operations handles statement and payment questions. |
King County Senior, Disabled, Veteran Exemptions and Deferrals
King County provides tax relief information for seniors, persons with disabilities, and disabled veterans. The Assessor’s office recommends applying online when possible because paper applications can take longer to process.
Eligibility depends on income, age or disability/veteran status, ownership, occupancy and program-specific rules. Use the official portal or call the exemptions team before assuming you qualify.
| Program | Basic Idea | Important King County Detail |
|---|---|---|
| Senior or disabled exemption | May reduce property taxes for eligible seniors, disabled persons or qualifying disabled veterans. | King County lists an income limit under $84,000 based on 2025 earnings for the exemption page. |
| Deferral | Lets eligible owners pay taxes later instead of receiving an immediate reduction. | King County lists deferral eligibility for age 60 or older, retired because of physical disability, ownership/occupancy, income and equity requirements. |
| Limited-income deferral | A state-linked route where qualifying limited-income owners may defer part of property taxes. | King County’s 2026 calendar lists September 1 for limited-income deferral applications. |
| Destroyed property relief | Relief may apply when property is damaged or destroyed by events such as fire, flood or earthquake. | Involuntarily destroyed property may qualify for current-year relief; voluntary destruction timing can be different. |
- Open King County’s senior or disabled exemptions page.
- Check current income, age, disability, veteran, ownership and occupancy rules.
- Use the online senior exemption portal when eligible.
- Use paper forms only when online filing is not practical.
- Call exemptions staff if you need help with documentation or status.
Contact for exemption questions: King County lists Exemptions.Assessments@kingcounty.gov and 206-296-3920 for exemptions. Deferral questions may use the Assessor contact route listed by the county.
How to Appeal a King County Property Valuation
If you believe the Assessor made a mistake in valuing your property, King County recommends reviewing the property characteristics in eReal Property and contacting the Assessor’s office before filing an appeal. A correction may solve some errors without a full appeal.
Appeal petitions are generally due by July 1 of the assessment year or within 60 days from the mailing date on the value notice or other determination. The King County Board of Appeals and Equalization handles the appeal petition.
- Review your property characteristics in eReal Property.
- Contact the Assessor if the property data is wrong.
- Check the value notice mailing date and appeal filing deadline.
- Gather evidence before filing.
- File online through eAppeals or by mail to the Board of Appeals and Equalization.
- Save confirmation and watch for hearing instructions.
Evidence Checklist for a King County Property Tax Appeal
The best appeal evidence connects your requested value to market facts and property characteristics. Do not rely only on “my taxes are too high.” The board needs evidence showing why the Assessor’s value is not correct.
| Evidence | Best For | How to Use It |
|---|---|---|
| Comparable sales | Fair market value dispute. | Use nearby sales with similar land, improvement features and sale timing. |
| Recent purchase documents | New buyer value dispute. | Show sale price, sale date and arm’s-length terms. |
| Photos of condition | Damage, deferred maintenance or property-condition issues. | Date photos and connect each issue to value impact. |
| Repair estimates | Costly repairs affecting value. | Use contractor estimates, inspection reports or invoices. |
| Property characteristics correction | Wrong square footage, building grade, land size or use classification. | Compare eReal details with plans, permits, photos or records. |
| Independent appraisal | Higher-value, complex or contested valuations. | Use a report near the valuation date when possible. |
King County Personal Property, Mobile Homes and Business Assets
King County Treasury explains that real property includes land and structures, while personal property includes assets used in conducting a business. Mobile homes and floating homes may be taxed as personal property if they are not associated with a real property account.
Business personal property users should watch the April 30 listing deadline and use King County’s eListing system when applicable. Personal property tax payment and delinquency instructions can differ from real property.
| Property Type | What It Means | What to Do |
|---|---|---|
| Real property | Residential or commercial land and structures. | Use eReal Property for characteristics and the payment portal for bills. |
| Business personal property | Assets used in conducting business. | Use eListing and keep asset records, costs and location details. |
| Mobile homes | May be taxed as personal property if not tied to a real property account. | Call the mobile home/personal property tax line for account-specific payment instructions. |
| Floating homes | May be taxed as personal property if not associated with a real property account. | Check account type before using real property payment instructions. |
- Open King County eListing if reporting business personal property.
- Confirm whether the account is real property or personal property.
- Use the correct Treasury phone number for payment questions.
- File appeal by the deadline shown on the valuation notice if value is wrong.
Late King County Property Taxes, Payment Plans and Foreclosure Risk
If first-half taxes are not paid by April 30, King County says monthly late charges are calculated under state law. If second-half taxes are not paid by October 31, monthly late charges begin on November 1.
King County cannot grant payment extensions for hardship. Payment plans may be available for delinquent taxes, but plans have rules and do not replace the current-year due dates.
| Late Issue | What It Means | What to Do |
|---|---|---|
| First half missed | Late charges may be calculated after April 30. | Use the payment portal for exact real-property balance before paying. |
| Second half missed | Monthly late charges begin on November 1 for unpaid second half. | Pay through the official portal or contact Treasury immediately. |
| Personal property delinquent | Online partial delinquent payment options may differ from real property. | Call 206-263-2844 for personal property amount and instructions. |
| Payment plan | King County offers payment plans for delinquent prior-year taxes through a signed agreement. | Contact PaymentPlans@kingcounty.gov or the foreclosure/payment plan phone line. |
| Foreclosure risk | Real property with taxes three or more years delinquent may become subject to foreclosure action. | Contact King County Treasury Foreclosure Unit immediately. |
- Search the account again in the official payment portal.
- Confirm tax year, unpaid installment and late charges.
- Call Treasury if the account is personal property, mobile home or commercial personal property.
- Ask about payment plan rules only after taxes are delinquent.
- Do not ignore foreclosure or lien-related notices.
Mortgage Escrow and Missing Payment Problems
Even if a mortgage company pays your taxes, King County says it is the owner’s responsibility to make sure property taxes are paid on time. Mortgage processors often submit payments close to the deadline.
If your payment does not show as paid after the due date, check the official account and contact your mortgage company. King County FAQ advises contacting the mortgage company if the payment is still not showing as paid by ten days after the due date.
Ask the lender for tax disbursement proof, parcel number and payment date.
Search the official King County account and call Treasury if the balance looks wrong.
Gather county receipt, lender proof and bank/card confirmation before requesting correction.
Check closing statement, tax proration and county account status after recording.
Destroyed or Damaged Property Tax Relief
King County has a destroyed property relief route for property damaged or destroyed by events such as fire, flood or earthquake. Relief timing depends on whether the destruction was involuntary or voluntary.
If your property was damaged, do not wait until the next bill. File the official claim route, keep photos, insurance documents, repair estimates, inspection reports and dates of damage.
- Open King County destroyed property relief.
- Confirm whether the damage was voluntary or involuntary.
- Gather photos, repair estimates, insurance and inspection records.
- Complete the official destroyed property form.
- Track the determination and appeal if needed.
Common King County Property Tax Mistakes to Avoid
Most problems happen because owners use the wrong office, miss an appeal deadline, assume escrow paid, or do not save proof of payment or valuation evidence.
Appeal value through Assessments and BOE. Pay bills through Treasury Operations.
The appeal window usually starts with the valuation notice, not the later tax statement.
Use KingCounty.gov or Payment.KingCounty.gov to avoid look-alike payment pages.
Owners remain responsible for confirming tax payment posting.
Personal property, mobile homes and commercial personal property may have different payment handling.
Late charges are calculated monthly. Use the official portal for the exact current amount.
King County Property Tax Contacts
Use the right contact based on the task. Payment and account balance questions belong with Treasury Operations. Assessment value, valuation notice and property characteristic questions belong with the Department of Assessments.
| Need Help With | Official Contact | Phone or Email |
|---|---|---|
| Real property tax payment | King County Treasury Operations | 206-263-2890; PropertyTax.CustomerService@kingcounty.gov |
| Mobile home, personal or commercial property tax | Treasury Personal Property | 206-263-2844; Treasury.PersonalProperty@kingcounty.gov |
| Assessment value or property characteristics | King County Assessor | 206-296-7300; Assessor.Info@kingcounty.gov |
| Senior or disabled exemption | Assessor Exemptions | 206-296-3920; Exemptions.Assessments@kingcounty.gov |
| Appeal petition | Board of Appeals and Equalization | 206-477-3400; BOE@kingcounty.gov |
| Appeal assistance | King County Property Tax Advisor | 206-477-1060; taxadvisor@kingcounty.gov |
King County Treasury Operations: King Street Center, 201 South Jackson Street, Seattle, WA 98104. Regular public counter hours shown by the payment portal are Monday through Friday, 8:30 AM to 4:30 PM.
Related Property Tax Guides on This Site
These internal guides can help you understand the wider property tax process before using official King County systems.
Official King County Washington Property Tax Links
Use these official links when you are ready to complete an account-specific action, pay a bill, search property records, apply for tax relief, file an appeal or contact the correct office.
King County Washington Property Tax FAQs
Where do I pay King County Washington property tax?
Pay through King County Treasury Operations using the official King County property tax payment portal. You need a tax account or parcel number.
When are King County property taxes due?
First-half taxes are due April 30, and second-half taxes are due October 31. If the date falls on a weekend or King County holiday, taxes are due the next business day.
What if my total King County tax is less than $50?
King County’s 2026 property tax page says if taxes are less than $50, full payment is due April 30.
How do I search King County property tax records?
Use eReal Property for valuations, property characteristics, levy rates and sale history. Use the payment portal for tax bills, balances and receipts.
Can I search by address?
Yes. King County property information tools allow address-based research through eReal Property and related property lookup systems. The payment portal may require a tax account or parcel number.
Who handles King County property tax payments?
King County Treasury Operations handles property tax billing, collecting, distributing and reporting for real and personal property tax accounts.
Who handles King County property value?
The King County Department of Assessments handles valuation, property characteristics, value notices, eReal Property and many tax relief programs.
What is eReal Property?
eReal Property is King County’s property information search tool for valuations, property characteristics, levy rates and sale history.
How do I appeal a King County property valuation?
Review the property in eReal, contact the Assessor if property characteristics are wrong, then file with the Board of Appeals and Equalization online through eAppeals or by mail.
What is the King County property tax appeal deadline?
Appeal petitions are generally due by July 1 of the assessment year or within 60 days from the mailing date on the value notice or other determination.
What evidence helps a King County appeal?
Comparable sales, recent purchase documents, photos, repair estimates, property-characteristic corrections, appraisals and market evidence can help support a valuation appeal.
What is the King County senior or disabled exemption?
It is a tax relief program for qualifying seniors, persons with disabilities and certain disabled veterans. Eligibility depends on income, age or disability/veteran status, ownership and occupancy rules.
What income limit does King County list for senior or disabled exemptions?
King County’s exemption page lists an annual income limit under $84,000 based on 2025 earnings for the exemption program. Verify current-year details before applying.
Does King County offer property tax deferrals?
Yes. Deferrals may allow eligible owners to pay taxes later, but deferred taxes and interest become a lien until repaid.
What if my property was damaged or destroyed?
King County has a destroyed property relief route. Involuntarily destroyed property such as fire, flood or earthquake damage may qualify for relief in the year of destruction.
What is King County personal property tax?
Personal property includes assets used in conducting business. Mobile homes and floating homes may be taxed as personal property if not associated with a real property account.
When are King County personal property listing forms due?
King County’s 2026 property tax calendar lists personal property listing forms due April 30.
Can I pay King County property tax by phone?
King County FAQ says they cannot process property tax payments over the phone, but staff can talk taxpayers through the online payment process.
Can I get a payment extension for hardship?
King County FAQ says extensions cannot be granted due to hardship or other extenuating circumstances. Payment plans may be available for delinquent taxes.
What happens if King County property taxes are late?
Monthly late charges apply after the due dates. First-half delinquency begins after April 30, and second-half delinquency begins after October 31.
Does mortgage escrow guarantee my taxes were paid?
No. King County says the property owner remains responsible for making sure taxes are paid on time. Check the county account and contact the mortgage company if payment is not posted.
What is the King County payment service fee?
King County’s payment page says debit and credit card payments are subject to a 2.35% service fee with a $2.00 minimum beginning January 1, 2026.
Where is King County Treasury Operations located?
King County Treasury Operations is at King Street Center, 201 South Jackson Street, Seattle, WA 98104.
Is CountyPropertyTaxes.us an official King County website?
No. This is an independent informational guide. Use official King County, Washington state, and county payment pages for final account-specific actions.
Bottom Line
For King County Washington property tax, use Treasury Operations for bills, payments, receipts and delinquent balances. Use the Department of Assessments for value, property characteristics, exemptions, deferrals, destroyed-property relief and valuation notices. File appeals by the official July 1 or 60-day deadline route.
Pay TaxesSearch RecordsDue DatesExemptionsAppealsOfficial Links