Helpful Links

Prosser Office

620 Market St

PO Box 630

Prosser, WA 99350

© 2017 by Benton County Treasurer

Kennewick Office

5600 W Canal Dr Ste A

Kennewick, WA 99336

Phone: 509-786-2255 or 509-735-8505

Email: Treasurer@co.benton.wa.us

Hours: 8:30am - 4:30pm Monday - Friday

Using This Site

  • Facebook
  • Twitter

Payment Due Dates

The entire year’s tax is due on or before April 30th. You may choose to pay half by April 30th and half by October 31st (if applicable). Interest and penalty will be charged on the entire principal balance. Real and Personal Property taxes less than $50.00 are due in full by April 30th. By Washington State law, the postmark is considered the received date for interest calculations. (RCW 1.12.070)