The Parcel Information Search Tool allows you to view limited assessment data. The tool allows you to search by either assessor’s parcel number (APN) or by street address. Some parcels, such as vacant land, have not been assigned street addresses, and an APN will be necessary to perform a search. Please note that you may need to change the county to Mariposa at the beginning of the search.


When a transfer occurs, the Assessor receives a copy of the deed and determines if a re-appraisal is required under state law. If it is required, an appraisal is made to determine the new market value of the property. The property owner is then notified of the new assessment and has the right to appeal the value.

Supplemental Assessment

State law requires the Assessor’s Office to re-appraise real property immediately upon change in ownership or completion of new construction. The Assessor’s Office must issue a supplemental assessment, which reflects the difference between the prior assessed value and the new assessment. This value is prorated based on the number of months remaining in the fiscal year, ending June 30. This supplemental assessment is in addition to the regular tax bill. Notices of the supplemental assessment are mailed out to the property owners prior to the issuance of the tax bill.

Homeowners’ Exemptions

If you own and occupy your home as your principal place of residence, you may apply for an exemption of up to $7,000 of the assessed value. New property owners are automatically sent an exemption application in the mail. Homeowners’ Exemptions may also be claimed on a supplemental assessment if the property was not receiving an exemption on the prior assessment roll.

Exemption Claim Form (PDF)

Parent / Child Exclusion

The transfer of a principal place of residence between parents and children may be excluded from re-appraisal on timely filing of an application. Certain restricted transfers between grandparents and grandchildren whose parents are deceased may also be excluded from reassessment on timely filing of an application.

Exclusion Claim Form (PDF)

Mobile Homes

All new mobile homes purchased after June 30, 1980 and those on permanent foundations, are subject to property taxes. As with real property, the assessed value on mobile homes cannot be increased more than 2% annually, unless there is a change in ownership or new construction. Mobile Homes bought before June 30, 1980 are generally not subject to property taxes. They are on license fees, which are under the jurisdiction of the State Department of Housing and Community Development. They can be reached toll free at 800-952-8356.


Vessels and aircrafts are taxable and appraised annually to the owner as of the lien date of January 1. The value is determined by reviewing the purchase prices and sales of comparable vessels and aircraft. Location and ownership information is obtained from the Department of Motor Vehicles, the Federal Aviation Administration, and on site inspections.

Aircraft of historcal significance may be exempt from property taxes. Some of the requirements that must be met for the aircraft to qualify for this exemption include:

  • Aircraft must be at least 35 years old, or one of fewer that five that exist worldwide.
  • MUST be owned by an individual (NOT a corporation or partnership)
  • May not be used for general transportation purposes
  • Must have been publicly displayed at legitimate events at least 12 times during the preceeding calendar year
  • Exemption affidavit MUST be filed with the Assessor annually by February 15