Mailed & Postmarked Payments

Penalties for Payments Received AFter Delinquency Date

Property tax payments must be received or postmarked by the delinquency date to avoid penalties. If a payment is received after the delinquency date with no postmark, the payment is considered late and penalties will be imposed, in accordance with State law. 

  • If the 1st installment is late, a 10% late penalty will be imposed. 
  • If the 2nd installment is late, a 10% plus $20 cost will be imposed.


Postmarks are imprints on letters, flats, and parcels that show the name of the United States Postal Service (USPS) office that accepted custody of the mail, along with the state, the zip code, and the date of mailing. The postmark is generally applied, either by machine or by hand, with cancellation bars to indicate that the postage cannot be reused.

Taxpayers who send their payments by mail are cautioned that the USPS only postmarks certain mail depending on the type of postage used, and may not postmark mail on the same day deposited by the taxpayer.

Postmarked Postage

Postage Without Postmarks

If you use these types of postage, the USPS will not postmark your mail. You will be charged a 10% penalty and a $20 cost, if applicable, if we do not receive your mailed payment by the delinquency date.

Other Options

  • Purchase and complete a Certificate of Mailing (PDF) from the USPS, which is a receipt that provides evidence of the date that your mail was presented to the USPS for mailing. It can only be purchased at the time of mailing through the USPS. The USPS charges a fee for this service.
  • Purchase a Postage Validated Imprint (PVI) (PDF) label from a USPS retail counter or window. The PVI is applied to a piece of mail by personnel at the retail counter or window when postage has been paid to mail that item. The item is retained in USPS custody and is not handed back to the customer. The date printed on the PVI label is the date of mailing.

Mailing Payments

Payments must be postmarked before the delinquent date to avoid penalties. Please mail payments to:

P.O. Box 247

Mariposa, CA 95338

Payments In Person

Payments may also be made in person between the hours of 8 a.m. and 5 p.m., Monday through Friday, holidays excepted. Please deliver payments to:

Mariposa County Tax Collector’s Office
4982 10th Street
Mariposa, CA 95338

Pay by Credit Card or E-Check

You may pay online. Use your twelve-digit ASMT Number (Assessment Number)  and/or your Fee Number to make a payment. Lexis Nexis web payments are charged 2.5% (minimum of $2.50) to pay by credit card, 1% to pay by Debit or pay by e-check for FREE.