Interbay property taxes track Seattle’s 0.99 percent effective rate, but the King County mass-appraisal model misfires on Interbay homes in distinctive ways. Here is how to spot it.
Interbay is the industrial-and-commercial belt between Magnolia and Queen Anne, with a golf course, the National Guard Armory, and very little single-family residential. The 2026 King County Assessor median assessed value across Seattle is $833,000 at an effective rate near 0.99 percent, producing a citywide median bill around $8,000 — but the bill that lands on an Interbay home depends on the model’s neighborhood-level math, which is where the gaps appear.
How are Interbay property taxes calculated?
King County reassesses every Seattle property every year, including every parcel in Interbay. The Assessor’s mass-appraisal model weights square footage, year built, lot size, and recent neighborhood sales, then applies the combined Seattle levy rate (around 0.99 percent for 2026) to the result. Voter-approved levies for schools, transit, parks, and city services layer on top of the state and county base.
What the model rarely picks up are the property-specific and Interbay-specific factors that buyers actually price into offers — and that is where most appeals are won. Anchored by the BNSF rail corridor, Interbay Golf Center, and 15th Avenue West, Interbay’s housing stock has its own quirks the citywide model does not always capture.
Where does the Assessor get Interbay wrong?
Interbay's residential parcels sit at the center of two big future changes: Sound Transit's planned Ballard Link extension (which would put a station in Interbay) and the long-running Magnolia Bridge replacement project. Both add uncertainty that buyers price in at a discount. The mass-appraisal model has not absorbed either factor.
For homes within a few blocks of the planned Ballard Link station alignment along 15th Avenue West, document the construction-period uncertainty with Sound Transit's published timeline. For Magnolia Bridge proximity, the uncertainty around the replacement design and its eventual alignment is real and ongoing. Combined, these create a documentable discount that Interbay's small single-family pocket faces but the model does not credit.
Interbay single-family comps to the western edge of Queen Anne and the eastern edge of Magnolia. A tight comp set drawn from genuinely similar homes — same submarket, similar size and age, similar condition — is what moves an Interbay appeal at the King County Board of Equalization.
What does an Interbay appeal actually look like?
Interbay homeowners appeal through the King County Board of Equalization, the same independent panel that hears every Seattle and King County appeal. The 2026 filing window runs through July 1, or 60 days after your Official Property Value Notice mails, whichever is later. The hearing is short, usually 15 to 30 minutes by phone, and the Board wants concrete evidence: comparable sales, documented condition issues, or an outright error in the property record.
For the broader Seattle context, see the Seattle property taxes guide or the 2026 King County property tax appeal guide.
Is an Interbay appeal worth filing?
At Seattle’s 0.99 percent effective rate, every $10,000 of assessed-value reduction is roughly $100 off the annual bill. A 10 percent reduction on a typical Interbay home (recent sale prices around $850,000, assessed values somewhat lower) pulls roughly $800 a year off the bill, and reductions tied to documented evidence often land larger. Most Interbay homes have at least one angle worth pursuing — the question is which one.
FairAppeal handles the full process from review through hearing, and only charges a percentage of first-year tax savings if the appeal actually reduces your taxes. Enter your address on the homepage for a free review — the 2026 window is still open.