Taxman Is Knocking Across Contra Costa County

CONTRA COSTA COUNTY, CA — It's that time of year in Contra Costa County — and we're not talking about the holiday season.

Instead, property owners are reminded that the first installment of property taxes becomes delinquent if not paid by Dec. 10, 2025, and the second installment becomes delinquent if not paid by April 10, 2026.

Late payments will incur a 10% penalty. In addition, an administrative cost will be added on late second installment payments, according to the county.

The pocketbook pain is real, but the county said it is making it as quick and easy as possible for residents to meet their property tax obligations.

Property taxes can be paid online, by phone, by mail, and in person at the County Finance Building, 625 Court St., Room 100, in Martinez.

Payments can also now be made at a new drive-through drop box also located at the Financial Building, 625 Court St. — on the Main Street side — also in Martinez. The box is available 24-hours a day, every day, until 5 p.m. on December 10th and April 10th. Use the envelope provided in your tax bill and enclose your installment payment coupon with a check. Do not deposit cash.

Mailed-in payments should be addressed to the appropriate address with the required information including an APN number. Check with the Treasurer's office for more information.

For more information, visit www.cctax.us or call (925) 608-9500.

Annual tax bills were mailed in October.

Not receiving a bill does not exempt property owners from payment or penalties, according to the county.

For more information, visit www.countytreasurer.org.

Contra Costa County created how-to videos in English and Spanish with more details.