Assessor Maps

An assessor's parcel number is a series of twelve numbers/digits that are used as a file number to inventory or identify property (012-345-678-000)

• The first three numbers of the series identify the map book the real property is located in
• The next three digits represent the page number and block within the map book
• The next three digits are used to identify the number assigned to a parcel
• The last three digits are zero

These can be accessed via the online Assessor Portal or in the Assessor’s office.

This information can be found by checking the most current published assessor parcel map or by contacting our office. Contact us at 707-565-1888 or assessor@sonoma-county.org.

Parcel number changes become effective in the tax roll year following the tax roll year in which they are completed. For example, a parcel number change completed in July 2022 (during the 2022-2023 tax roll year) will be effective for the 2023-2024 tax roll year and the annual property tax bill that will be mailed in October 2023.

Assessor Parcel map are for assessment purposes ONLY. To identify the physical boundaries of your property, you will need to contact a licensed land surveyor or civil engineer.

A copy of the legal description for your property may be found on the most recent recorded deed. If you do not have a copy of your deed, you can get a copy from the Sonoma County Clerk-Recorder's Office or search their records online.

If you are unable to locate this document, it is recommended you contact a title company. 

There are several reasons an assessors parcel may not be the same legal parcel. If you have questions regarding a particular parcel and why it is represented a certain way, you may contact our office here.

Addresses are assigned by Permit Sonoma or local City planning department.

Easements can be created by maps, by deeds, or by agreements between parties. An easement may be referenced in the legal descriptions of a recorded deed. Documents creating easements may be recorded separately from or after the original deed is recorded. Often the easiest way to locate an easement is by obtaining a preliminary title report from a title company. Easement information is not maintained on the assessor’s parcel maps. For public easement information, contact the Planning Department of the jurisdiction where the property is located.

The Mapping Section processes deeds/maps in the date order they are recorded, approximately 6 months in arrears. This means that if a document or map records January 1st of a given year, it will not be acted on for at least 6 months. Processing times may vary due to workload and timing in relation to the annual tax roll preparation processes. New assessor parcels are not created during May and June of each year due to annual tax roll preparation processes. Contact our office at (707) 565-1888 and a member of our Mapping staff will provide an estimate of when the new number(s) will be available.

Not necessarily. The assessor’s maps are developed and maintained for assessment purposes only. You must contact the Plannin​g/Permit Department of your local jurisdiction to confirm the legality of a given parcel.

If you have a disagreement with your neighbor over the placement of a fence, this is a private civil matter that cannot be resolved by the Assessor. We recommend that you contact a licensed professional land surveyor for assistance at the License Look-up for California-Licensed Professional Engineers and Land Surveyors.

Contact the planning/permit department of your local jurisdiction to inquire about lot line adjustments, mergers, or other types of boundary modifications.

The Assessor mapping staff can assist you in locating relevant recorded information used in the production of our assessment maps, but we are not able to interpret those documents or do extensive research.

These images are produced by third parties for a variety of purposes. Unfortunately, the Assessor mapping department does not produce such imagery and won’t be able to interpret them. The Assessor parcel maps are based on recorded information. Please contact the image source with questions.