The King County tax auction is an online public sale where the county treasurer disposes of properties seized for unpaid property taxes, with the next sale scheduled for September 9, 2026. Parcels go to the highest bidder on a “where is, as is” basis, opening at a minimum bid equal to the delinquent taxes, interest, and costs owed. Winning bidders receive a tax deed, but that deed does not guarantee marketable title and does not wipe out every lien.
When and Where the Auction Happens
Washington law lets county treasurers sell tax-foreclosed property through electronic public auctions. King County’s primary vendor is RealAuction, at king.wa.realforeclose.com. The main foreclosure auction runs in September each year, with registration details and opening bids posted on the county’s website in mid-to-late August.
The county has also used Bid4Assets for reoffer sales and special auctions of parcels that didn’t sell the first time around. Reoffer sales run under different terms, including different deposit amounts and fee structures, so check which platform and which rulebook govern the specific sale you want to enter before you register.
Registering and Researching Parcels
To bid, you open an account on whichever platform is hosting that sale, enter vesting information (the exact name and address that will go on the deed), and submit a deposit plus a non-refundable processing fee. The deposit varies by auction. A recent Bid4Assets reoffer sale required a $300 deposit with a $35 processing fee; an earlier special sale on the same platform required $2,500. The main September auction’s deposit is announced when registration opens in August. Deposits must come in by certified check, money order, or wire transfer.
Once the deposit clears, you can view the parcel list. Expect the list to change up to the moment the auction starts, because owners frequently pay off their delinquent taxes at the last minute to stop the foreclosure. Use the parcel numbers to look up zoning, land use restrictions, and physical characteristics through the King County Assessor’s website and parcel maps. Check for recorded easements, environmental history, and development limits before you bid. The county disclaims any guarantee of condition, title, or fitness for use, and bidders who skip their own due diligence have no recourse after the sale.
How the Bidding Works
The auction runs over several days. Each parcel opens at a minimum bid equal to the total delinquent taxes, interest, and costs. You place bids through the platform, and most platforms offer proxy bidding: you set a maximum, and the system raises your bid by the minimum increment on your behalf. That spares you from watching every parcel around the clock.
As a parcel approaches its scheduled close, overtime bidding kicks in. A bid placed in the final minutes resets the clock for an additional window, often five minutes, so other bidders can respond. The clock keeps resetting until an extension passes with no new bids. Whoever is highest when the clock finally runs out wins.
Some auctions also charge a buyer’s premium, a percentage added on top of the winning bid. A recent King County reoffer sale on Bid4Assets charged a 5% premium. Whether a premium applies depends on the specific auction, and when it does, it becomes part of your total purchase price.
Paying and Receiving the Deed
Winning bidders must pay the remaining balance quickly, typically within a few business days of the sale’s close, and the deadline is enforced strictly. Miss it and you forfeit your deposit and may be barred from future auctions. Payment must come by wire transfer or certified check.
Your total includes the winning bid, any buyer’s premium, and administrative fees, which on some auctions include a per-parcel charge on top of the initial processing fee. After payment clears, you finalize vesting instructions on the platform. Get the name and address right the first time, because the county generally will not correct them once deed preparation begins.
The treasurer then executes a tax deed and records it like any other conveyance. The deed vests fee simple title in the buyer. Washington provides no general post-sale right of redemption for former owners, though minors and legally incompetent persons who owned the property at foreclosure may redeem within three years after their disability is removed. Keep the recorded deed in a secure place; you’ll need it for any future title insurance application or resale. Until recording is complete, do not enter the property or make physical changes.
One tax note on the purchase itself: Washington’s Department of Revenue lists transfers through foreclosure proceedings among the categories eligible for exemption from the Real Estate Excise Tax. The transfer still has to be reported, and you claim any exemption by listing the appropriate code on the REET Affidavit filed with the county.
What the Tax Deed Does Not Clear
Washington’s tax foreclosure wipes out most liens and encumbrances, and the statute says the tax deed conveys fee simple free from liens with limited exceptions. Federal tax liens are the exception that catches buyers off guard. A recorded IRS lien does not automatically disappear in a county tax sale.
Under federal law, the IRS has 120 days from the sale to redeem the property by reimbursing you the purchase price. If it does, you get your money back and lose the property. Even if the IRS does not redeem, the federal tax lien itself may remain attached, and you’ll have to work with the IRS to obtain a discharge or release before you can sell or finance. Check for federal tax liens in a title search before you bid.
A tax deed is also not what the title insurance industry treats as marketable title. Most title companies will not issue a standard policy on a tax-foreclosed property without further steps, because former owners or lienholders can still challenge the foreclosure. Buyers typically file a quiet title action in superior court under Washington’s quiet title statute, asking a judge to confirm ownership and extinguish any remaining adverse claims. An uncontested action generally takes several months; a contested one can take considerably longer. Attorney fees for a straightforward quiet title action commonly run from a few thousand dollars into the low five figures depending on complexity. Build this into your budget from the beginning. No action to set aside or cancel a tax deed may be brought more than three years after the deed is issued.
Occupants and Environmental Risk
The county does not remove occupants for you. Once your deed is recorded, you have standing to pursue an unlawful detainer action under Washington’s statute, which covers people who hold over or continue in possession after their right to the property has ended. That means hiring an attorney, filing in superior court, and following the state’s notice and service rules. The process costs money and takes time, so factor it into your bid if the property looks occupied. Changing the locks on your own is not a legal option and can expose you to liability.
Environmental contamination is another risk the auction price does not reflect. Under the federal Comprehensive Environmental Response, Compensation, and Liability Act, current owners can be held responsible for contamination that predates their ownership. CERCLA’s 2002 amendments created a “bona fide prospective purchaser” protection for buyers who conducted “all appropriate inquiries” before buying and who take “reasonable steps” to address ongoing or threatened releases. Qualifying at a tax auction generally means doing a Phase I Environmental Site Assessment before you bid. If the EPA funds a cleanup that raises the property’s fair market value, the government may place a “windfall lien” on the property, limited to the lesser of unreimbursed cleanup costs or the increase in value from the cleanup. For any parcel with industrial, commercial, or unknown prior use, a Phase I is cheap insurance against cleanup liability.
If You’re a Former Owner Looking for Surplus Funds
If a parcel sold for more than the total owed to the county, the former record owner can claim the surplus. The record owner at the time the certificate of delinquency was filed has three years from the date of sale to claim excess funds, and deeds or assignments recorded after the certificate of delinquency do not change who is entitled. If no claim is made within three years, the funds are deposited into the county’s current expense fund and all claims are extinguished. Washington law caps the fee any third-party “finder” can charge for locating these funds at 5% of the amount returned.