Agriculture

Williamson Act (Land Conservation Act)

Agricultural landowners who sign a contract with the County placing their land in the Williamson Act or Farmland Security Zone will have their agricultural land and living improvements assessed lower than their Proposition 13-factored value.

Parcel Maps

San Joaquin County Assessor parcel maps are available online. Assessment maps can also be obtained from the Mapping Department over the counter, via mail, fax, or email during office hours. There is a charge for this service.

Real Property

The value enrolled at the time the property is acquired (or the 1975 value if acquired before 1975) is the property’s base year value. This value is increased annually by a factor that is based on the California Consumer Price Index or 2%, whichever is less%. This value is referred to as the Proposition 13 value. Find more information about your assessed value here.

Decline in Value

In 1978 California voters passed a constitutional amendment (also known as “Prop 8”) that allows a temporary reduction in assessed value when a property suffers a “decline-in-value.”

Change in Ownership

The Office of the Assessor reviews all recorded deeds for that county to determine which properties require reassessment under the law. Find more information about changes in ownership and reassessment here.