Contra Costa County Property Tax Appeal Guide
If your Contra Costa County, CA property is over-assessed, you can appeal to lower your tax bill. Here are the deadlines, filing steps, and how often appeals succeed.
- Appeal deadline
- Jul 2 – Sep 15
- Appeal success rate
- 40%
- Effective tax rate
- 0.88%
- How to file
- Assessment Appeals Board application
- Pre-fillable appeal form
- County form required
How to appeal your assessment in Contra Costa County
Compare your assessed value to recent comparable sales. If your home is assessed above market value, gather 3–6 comparable sales and file your appeal with Contra Costa County before the deadline. A well-documented appeal with strong comps has the best chance of a reduction.
Check if you are over-assessed
Upload your assessment notice for an instant comparable-sales analysis, an over-assessment estimate, and a pre-filled appeal.
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For informational purposes only. Not legal, tax, or medical advice.