For property tax purposes you will need to know and use your AIN. The Assessor's Identification Number or AIN is the main indexing system used for property tax purposes. The AIN is a ten-digit number assigned to each piece of real property and is used on tax bills and correspondence to identify real property. The ten-digit AIN (1234-056-789) is made up of a four-digit Mapbook Number, a three-digit Page Number and a three-digit Parcel Number. You can locate your AIN various ways:

  • The AIN can be found on your deed
  • The AIN can be found on your "Annual Property Tax Bill” or “Supplemental Property Tax Bill”
  • The AIN can be found by entering your property address on the “Property Maps and Data” link or the “Property Sales and Maps” quick link from our internet homepage
  • The AIN can be found on your title report (which you received when you acquired title insurance)
  • The AIN can be found by contacting us at (213)974-2111, or toll free at (888)807-2111, option 6, or any of the Assessor’s Office Locations

You can also email us at helpdesk@assessor.lacounty.gov for assistance.