King County's new 2027 assessed values have reached Renton. I re-scored every single-family home in the city against its comparable sales. Here's what the county's own data shows.
The numbers
- 34,503 Renton single-family homes analyzed.
- 33,944 of them, 98.4% of the city, are now on 2027 values.
- 3,880 come back flagged as over-assessed in our scoring. 3,880 of 34,503 is 11.2%.
That 11.2% is below the county-wide flag rate of 14.9%. That's genuinely good news for Renton. It means the county's mass-appraisal model landed closer to the comparable sales here than it did in most cities. Most Renton homes look fairly assessed in our data, and if yours is one of them, my advice is to leave it alone.
Why the flagged homes still matter
Mass appraisal works at the population level. It misses at the individual level, because the model can't see what makes one house different from its neighbors. Those misses are what the 3,880 flags are: homes assessed above what recent comparable arms-length sales support.
Here's the part the county's own records make plain. Appeal rates scale with home value. Owners of homes under $500K file at 0.4%. Owners of $5M+ homes file at 10%, a 25x gap. The win rates barely move across that range: 22.6% at the bottom tier, 20.8% at the top. The Board of Equalization treats the cases about the same. The difference is who bothers to file.
Across all 15,630 petitions from 2021 through 2024, 21.9% ended in a reduction, about 1 in 5. Most appeals lose. But an average winning appeal at typical Renton price points is worth on the order of $954 a year in tax, per the Board's records for the $500K-1M tier. That recurs every year until the next revaluation.
Your appeal window
The deadline to appeal is July 1 of the assessment year, or 60 days after the date your value change notice was mailed, whichever is later. Use the mailing date printed on the notice, not the day it arrived. With Renton's new-value notices going out now, the 60-day clock is running for most of the city. After it lapses, the value stands until next year.
The honest caveat
Not every Renton home is on new values yet. 98.4% are; the rest are still assessed on their 2026 values while the county finishes its waves. County-wide, 82% of the homes we analyze are on 2027 values so far. If your notice hasn't arrived, any verdict you see today is scored against your 2026 value and can change when the new one lands. Check the tax year on your lookup before acting.
Every number above comes from King County's public assessment rolls and the Board of Equalization's published hearing records for 2021 through 2024. Nothing here is private data, just a close read of the public record.