On July 1, 1983, California State Law was changed to require the reassessment of property as of the first day of the month following an ownership change or the completion of new construction. In most cases, this reassessment results in one or possibly two Secured Supplemental tax bills being sent to the property owner in addition to the annual Secured property tax bill.
The Assessor first determines the new value of the property based on current market values. The Assessor then calculates the difference between the new value (set at the time of purchase or completion of new construction) and the old value (set on January 1 of the previous fiscal year). The result is the supplemental assessed value. Once the new assessed value of your property has been determined, the Assessor will send you a notification.