King County Property Tax Search: Look Up Bills, Records & Parcel Details
King County uses different tools for different property-tax tasks. The Assessor’s eReal Property system is best for property value, characteristics, parcel details, levy information and sales history. The Treasury property-tax system is where you check the tax account, statement, amount due, payment status and payment options.
If you only know the street address, start with eReal Property or Parcel Viewer. Once you identify the correct parcel or tax account number, move to the Treasury system before paying, checking escrow or relying on a balance.
Quick Answer: Which King County Search Should You Use?
If you need to identify a property, check its assessed value, review characteristics or find a parcel number, start with the King County Assessor.
If you need the current property-tax bill, amount due, payment status, statement or delinquent balance, use King County Treasury Operations.
Start with eReal Property or Parcel Viewer. Confirm the correct parcel before moving to the tax account.
Use eReal Property for assessment research or enter the parcel in the Treasury property-tax system to check the tax account.
Use the official Treasury tax account system. The assessment record is not the final payment balance.
Search the live Treasury account and check posted payments before sending a personal payment.
Use the Assessor to identify and understand the property. Use Treasury to understand what is currently owed or paid.
King County Property Search Tools: What Each One Does
King County has several property research tools. Choosing the right one prevents a common mistake: treating an assessment record as if it were the current property-tax bill.
For most homeowners, the shortest route is eReal Property → copy parcel/account information → Treasury tax account.
How to Search King County Property Tax by Address
Address search is useful when you do not have a tax statement, valuation notice or parcel number. Do not jump directly into a payment screen until you have matched the correct parcel.
- Open eReal Property.
- Use the property search route provided by King County.
- Confirm the address and parcel.
- Write down the parcel/account number.
- Do not pay until the Treasury tax account also matches.
An address is a starting clue. The parcel or tax account number is the stronger identifier for billing and payment.
How to Search by King County Parcel Number
King County parcel numbers are heavily used across assessment, GIS and tax systems. The Assessor’s eMap identifies the real-property parcel format as a 10-digit parcel number, while the Treasury payment system can work with parcel or tax account information.
Use the parcel to review valuation, property characteristics, levy information and sales history.
Use the parcel to see the property geographically and connect to related King County reports.
Use parcel/account information to retrieve the current tax account and payment details.
Do not add or remove digits casually. King County’s systems distinguish parcel numbers, real-property tax accounts and personal-property accounts. Use the number exactly as required by the specific official tool.
- Find the number on the tax statement, valuation notice, prior closing paperwork or Assessor record.
- Use eReal Property for assessment research.
- Use Parcel Viewer if you need a map check.
- Use Treasury for the current tax bill or payment record.
- Compare the property address before taking any financial action.
How to Look Up the King County Property Tax Account
The Treasury property-tax portal is the important final search when your goal is a bill, balance, payment, statement or delinquent amount.
King County says real-property tax account numbers are typically 10 or 12 digits. The payment portal instructs users not to include dashes when entering the account or parcel number.
- Prepare your parcel or tax account number.
- Open the Treasury property-tax system.
- Enter the number without dashes.
- Confirm the property/account before reviewing the bill.
- Check the live balance before paying or mailing a check.
The live Treasury account is more useful than an old statement when you need to know what is currently due.
What King County Property Search Results Can Tell You
Confirms which real-property parcel you are researching.
Use the physical location to make sure you selected the correct parcel.
Helps explain the assessment side of the tax process but is not the amount owed.
Useful for ownership research and valuation review.
Shows how local taxing districts and levy information relate to the parcel.
Use Treasury for the actual current bill, installments, posted payments and amount due.
Information-gain tip: If a bill rose sharply, compare both the Assessor record and the Treasury account. A value change and a levy/tax change are related but not identical explanations.
How to Find a King County Property Tax Statement
King County’s FAQ explains that you need the tax account number to obtain a tax statement. If you do not know it, use the Assessor’s property search first.
A saved tax statement is useful for records, but recheck the live account before paying because later payments or late charges can change the balance.
How to Check Whether King County Property Tax Was Paid
This matters most for owners with mortgage escrow, recent buyers, sellers, duplicate payments and taxpayers who mailed a check close to the deadline.
Compare the servicer’s disbursement record with the King County tax account.
Keep the online confirmation, bank record, canceled check or in-person receipt.
Make sure the posted payment belongs to the correct year and installment.
Do not pay again merely because an escrow payment has not appeared immediately.
King County notes that mortgage-company processing firms often submit tax payments during the final week before the deadline. If the mortgage payment is still not showing about 10 days after the due date, contact the mortgage company.
- Open the Treasury property-tax account.
- Search the parcel/account.
- Check the current tax year and posted payments.
- Compare the result with your escrow or bank record.
- Contact Treasury if the records do not reconcile.
2026 King County Property Tax Search and Deadline Calendar
Search and payment are connected because a current account tells you whether the first half, second half or a delinquent amount is outstanding.
If annual taxes are less than $50, the full amount is due. Keep payment or postmark proof.
Monthly late charges begin after the first-half deadline on delinquent taxes.
General BOE date; the later 60-day valuation-notice rule can also apply.
King County lists September 1 for limited-income deferral applications.
October 31 falls on a Saturday in 2026. King County’s FAQ says a weekend or county-holiday due date moves to the next business day.
Use Treasury to confirm the exact due amount and status rather than relying on a calendar alone.
Deadline rule: King County says first-half taxes must be paid or postmarked by the applicable April deadline and second-half taxes by the applicable October deadline. When a listed due date falls on a weekend or King County holiday, verify the next-business-day date on the current county page before mailing or paying online.
2026 King County Online Payment Fee
The official King County payment portal states that beginning January 1, 2026, debit and credit card property-tax payments are subject to a 2.35% service fee with a minimum fee of $2.00.
The fee is charged by the payment processor. King County states that it does not receive any part of that service fee.
Do not choose a payment method before checking the final fee. A large tax bill can make a percentage-based card fee significant. Review every available payment method in the official system before submitting.
A 2.35% processor fee on a $5,000 card payment would be $117.50. This is only a fee example; the official checkout screen controls the actual transaction fee.
Real Property Search vs Personal Property Tax Search
King County separates real property from taxable personal property used in business and certain mobile or floating homes.
Includes land and buildings such as homes, condos and commercial real estate. Use eReal Property and the parcel-based search workflow.
Generally includes business furniture, fixtures, machinery, equipment, supplies and certain mobile or floating homes.
King County’s payment system states that personal-property tax account numbers use a different format from real-property accounts. If you do not know the personal-property account number, contact the Assessor or Treasury rather than guessing from a real-estate parcel.
Do not use a real-property parcel workflow for a business personal-property or mobile-home-on-leased-land bill unless King County specifically links the account that way.
King County Property Tax Search Troubleshooting
Likely cause: address formatting, condo/unit issue or wrong search tool.
Next action: try Parcel Viewer or search from the official property information page.
Likely cause: multiple units, parcels or nearby addresses.
Next action: confirm map location, parcel number and property characteristics.
Likely cause: you are in the Assessor system rather than Treasury.
Next action: copy the parcel/account number and open the property-tax account.
Likely cause: recent sale, trust or processing delay.
Next action: match parcel and legal property details rather than relying on name alone.
Likely cause: processing timing or servicer issue.
Next action: compare Treasury account status with the mortgage disbursement.
Likely cause: late charges, later payment, correction or account update.
Next action: use the current online account as the working balance.
If the search problem is about property facts or assessed value, contact the Assessor. If it is about billing, balance, payment or receipt, contact Treasury.
What If the King County Assessed Value Looks Wrong?
The property-tax search can help you spot a value problem, but Treasury cannot generally fix the Assessor’s valuation.
- Prepare the valuation notice.
- Confirm the parcel number.
- Gather comparable sales and other evidence.
- Use eAppeal for eligible real-property appeals or follow the mail filing instructions.
- Save the filing confirmation.
Tax Relief: Search the Property Before You Apply
This search-focused page does not replace the full King County tax-relief guide, but the property record is still useful when checking whether an exemption or deferral appears correctly.
King County administers property-tax exemption programs for qualifying seniors, people with disabilities and disabled veterans.
A separate deferral program can postpone part of the tax under qualifying rules. Deferred tax and interest can become a lien on the property.
The current King County exemption page lists an annual income limit under $84,000 based on 2025 earnings for the exemption program. Deferral rules use separate qualifications and limits, so do not treat the two programs as interchangeable.
If the issue is a missing or incorrect exemption, start with the Assessor rather than the Treasury payment processor.
Records to Save After a King County Property Tax Search
Save it for assessment, GIS and future property research.
Save it for statements, payment questions and Treasury customer service.
Keep the current tax year copy for escrow, refinancing, sale and records.
Keep the receipt, bank record or mailing proof until the account shows payment.
Keep it if you may need to question the assessed value or file an appeal.
Keep the mortgage-servicer tax disbursement details if escrow handles payment.
King County Property Tax Search Contacts
King County Department of Assessments
Use for: property values, parcel information, characteristics, assessment questions and tax relief.
Phone: 206-296-7300
Senior exemptions: 206-296-3920
Address: King Street Center, 201 South Jackson Street, Seattle, WA 98104
Typical listed hours: Monday–Friday, 8:30 a.m.–4:30 p.m.
King County Treasury Operations
Use for: tax accounts, bills, statements, payments, receipts, delinquent balances and payment questions.
Property Tax Customer Service: 206-263-2890
Personal property/mobile homes: 206-263-2844
Foreclosure: 206-263-2649
Mail: King County Treasury Operations, 201 South Jackson Street #710, Seattle, WA 98104
Office details can change. Use the official King County page before making a time-sensitive visit or mailing a deadline payment.
Official King County Property Tax Search Links
Open the Assessor tools first when you need to identify the property. Open Treasury only after you have a confident parcel/account match and need a bill, payment status or balance.
King County Property Search Terms
- Parcel Number
- The real-property identifier used across King County assessment, GIS and property research tools.
- Tax Account Number
- The account identifier used for King County Treasury billing and payment functions.
- eReal Property
- The King County Assessor’s online property-information system.
- Parcel Viewer
- King County GIS map search used to identify parcels by address, parcel number or map location.
- Valuation Notice
- The Assessor notice showing value information and an important date for calculating the assessment appeal filing period.
- Tax Statement
- The tax document or online account information used to review current charges and payment details.
King County Property Tax Search FAQs
How do I search King County property tax records by address?
Use King County eReal Property or Parcel Viewer when you only know the address. Confirm the parcel, then copy the parcel or tax account number and use the official King County Treasury property tax system to view the current tax account, statement, balance or payment status.
What is the difference between a King County parcel number and tax account number?
The parcel number identifies the real-property parcel in assessment and mapping systems. The tax account number is used for billing and collection. King County real-property tax account numbers may be 10 or 12 digits, while business or other personal-property accounts use a separate format.
Can I see whether my mortgage company paid King County property taxes?
Yes. Search the official King County property-tax account and review posted payment information. King County advises property owners to confirm taxes are current even when a mortgage servicer pays from escrow.
When are King County property taxes due in 2026?
The normal King County schedule uses April 30 for the first half and October 31 for the second half. If a due date falls on a weekend or King County holiday, the county states that payment is due the next business day. Check the live account and current-year county instructions before paying near a deadline.
What should I do if my King County property value looks wrong?
Start with the King County Assessor rather than Treasury. Review the eReal Property record and valuation notice. Assessment appeals generally must be filed with the King County Board of Equalization by July 1 of the assessment year or within 60 days of the valuation notice mailing date, whichever is later.
Bottom Line
For a King County property tax search, use the Assessor tools to identify the parcel and understand the property, then use the Treasury tax account for the current statement, amount due and payment status. Verify the parcel, tax year and escrow status before paying, and use the Assessor or Board of Equalization if the real problem is assessed value rather than the bill.
Search by Address Search Parcel View Tax Account 2026 Dates Appeal Help Official LinksMaterially researched and updated: August 26, 2026.