This office does not do field work such as surveying property lines or creating Records of Survey. Data on the maps comes from recorded documents. This includes plat maps, subdivision maps, deeds, and other documents. Legal descriptions and recorded documents used by Mapping are available through the Recorders Office. Fence issues do not fall within the jurisdiction of the Assessor.
Real property is assigned a unique identification number called an Assessor Parcel Number (APN). The APN is used by the Assessor-Recorder, other County offices, and other businesses. The Assessed Value Lookup page will also show the APN when searching by an address. View Parcel Maps with your APN. Understanding how parcel numbers are organized will help with finding parcels that do not have an address.
Sometimes parcels and their APN change. Typical reasons for parcel and APN changes include combination with other parcels, division into smaller parcels, re-survey or reorganization resulting in a significant boundary change, or re-numbering parcels to alleviate "overcrowding" on a map page or map book.