Are you overpaying property tax?
CompFinder finds the comparable sales and builds the evidence for your property tax appeal — in seconds. Finding comps just got 50× easier.
Covering San Francisco, Oakland, San Jose, Seattle, and Issaquah.
Easy
Type your address. No spreadsheets, no MLS access, no appraiser jargon.
Fast
Appeal-ready comparable sales and analysis in seconds, not weekends.
Compelling
Comps chosen and explained the way an assessment appeals board weighs them.
Low cost
A fraction of what a consultant or appraiser charges for the same evidence.
How CompFinder finds your property tax appeal comps
Enter your address
We pull the property record and recent nearby sales for your market.
AI selects the comps
It weighs location, type, size, age, condition, views, and floor to find the strongest comparables near your valuation date.
Get your evidence
A clear, appeal-ready analysis you can take to your county assessment appeals board.
Property tax appeals in San Francisco, Oakland, San Jose, Seattle, and Issaquah
CompFinder supports 2026 comps for condos and single-family homes in these areas, with more being added. Don't see yours? Tell us where to go next.
Frequently asked questions
What is CompFinder?
CompFinder is an AI tool that finds comparable home sales (“comps”) and builds the evidence package for a residential property tax appeal. You enter your address; it pulls property data, selects the most relevant recent sales, and produces an appeal-ready analysis in seconds.
How do I appeal my property taxes?
Generally: (1) check your assessment notice for the assessed value and appeal deadline, (2) gather comparable sales near your valuation date that are similar in location, type, size, age, and condition, (3) prepare a clear comparison showing your assessed value is too high, and (4) file with your county assessment appeals board before the deadline and present your evidence. CompFinder automates the comp research and analysis steps.
What makes a good comparable sale for a property tax appeal?
Strong comps are arms-length sales close to the valuation date, in the same neighborhood, of the same property type (condo vs. single-family), with similar square footage, bedroom/bathroom count, age, condition, and features such as parking, views, and floor level. Avoid foreclosures, short sales, and transactions between related parties.
When is the property tax appeal deadline in California?
For most California counties, the regular assessment appeal filing window is July 2 through September 15 (or November 30 in some counties). California Revenue & Taxation Code §402.5 also bars sales dated more than 90 days after the lien date from being used as comparables. Always confirm the exact date on your county assessment notice.
Which areas does CompFinder cover?
CompFinder currently covers San Francisco, Oakland, and San Jose in California, and Seattle and Issaquah in Washington (King County), with more markets being added.
Is CompFinder legal, tax, or financial advice?
No. CompFinder provides comparable-sales data and analysis to help you build your own case. It does not provide legal, tax, or financial advice; consult a qualified professional before making decisions.