Frequently Asked Questions - Sonoma County Assessor

How can I find out who owns a piece of property?

You can look up property at the Assessor's Office in one of three ways:

by situs (street address)
by parcel number
by owner name

If you know one of the three, you can visit our office and use the Assessor's computerized property data system to determine the other two.

If you know the parcel number, you can also call our Interactive Voice Response system at (707) 565-3010 and have basic Assessment Roll information about the parcel read back to you or faxed back to a FAX number you specify.

You can also look up basic Assessment Roll information on-line. Visit the section of this web site titled "Search the Assessment Roll" for more information.

Or if you prefer, you can contact us by telephone at (707) 565-1888 during our regular office hours and we will assist you.

How can I lower my property taxes?

There are a variety of options available for lowering your property taxes. Each of these exemptions, exclusions or provisions has specific qualifications:

Homeowner Exemption
Parent/Child Transfer Exclusion
Replacement Residence Exclusion
Grandparent/Grandchild Transfer Exclusion
Veteran and Disabled Veteran Exemption
Property Value Decline Provision
Property Tax Postponement for Seniors or Disabled Citizens
Disaster Provision
Builder Exclusion

Please contact us for more information.

What is a supplemental assessment?

The County Assessor must appraise property at its market value on the date of a change in ownership or when new construction is completed. The difference between the property's newly determined value after one of these events and the value which was previously enrolled on the Annual Assessment Roll results in a supplemental assessment. For more information, contact our office.

What kinds of information can you provide to the public?

In addition to basic Assessment Roll information such as owner names, property addresses, and assessed property values, the County Assessor can provide a variety of data about Sonoma County properties to interested parties. Parcel maps, various detailed reports, and other kinds of information are available for purchase. Please contact us for more information.

Will my home be reappraised if I add another bedroom?

Your entire home will not be reappraised if you add on another room. Only the value of the new addition will be added to your assessed value.

If I get married, will my house be reappraised?

Your home will not be reappraised if you add your spouse as a joint tenant on the deed to your property. Interspousal transfers do not result in reappraisals.

I added a room and did the work myself. Will I be assessed only on cost of materials?

No. New construction is assessed at the market value it adds to property.

I just bought a house. Will I be assessed on the price I paid?

Not necessarily. Real property is valued at its current market value at the time it changes ownership. In a majority of cases, the sales price equals market value, but not always. The unpaid balance of any improvement bonds on the property is included in the market value.

How do I add someone to my title?

We recommend that you get legal advice on this topic or discuss questions of this nature with a title company.

Are the parcels on the Assessor's maps "legal" parcels?

Not necessarily. The Assessor's maps are developed and maintained for property tax administration purposes only.

Why doesn't the Assessor split parcels with a Certificate of Compliance?

A Planning Department Certificate of Compliance signifies that the Planning Department would recognize the affected parcels as being "legal" if they were to be split or sold, but this certificate doesn't pertain to changes in value or ownership.

What if I don't agree with my property value assessment?

The first thing you should do is discuss your concerns with us. If we are unable to reach agreement about the value of your property, you can file an appeal with the Clerk of the Board of Supervisors. Appeals are heard regularly by the independent Appeals Board. If you wish, you can download an Application for Reduced Assessment and also the Board of Equalization's guide to Residential Property Assessment Appeals.