Weights & Measures


The mission of the Napa County Department of Weights and Measures is to provide fair competition and equity in the marketplace and to ensure that the interests of the buyer and seller are protected through educational, inspection and enforcement programs.

 The Napa County Department of Weights and Measures is divided into several programs to:

  • Ensure the accuracy of commercial weighing and measuring devices
  • Verify the price, quantity and labeling of packaged and bulk commodities
  • Verify quality, advertising and labeling standards for various petroleum products
  • Enforce Weighmaster laws to assure accuracy of information on Weighmaster certificates.

Enjoy this informative video to see how Weights and Measures protects consumers, workers, and businesses. 

Consumer Complaint

To submit a Weights & Measure Complaint fill out the Online Form

To Submit a CDFA Air & Water Complaint visit the CDFA website

Contact Us

Napa Office: 707-253-4357

Yountville Office: 707-299-1426

Email: Weights & Measures Email

Registered Service Agent Examination

Anyone wishing to take the RSA exam on or After April 1, 2013 must take the test online at DMS Registered Service Agency (select Registered Service Agent Online Exam link on the right- hand side of the page).

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