Under Proposition 13, newly constructed property (only the portion that is newly constructed) is appraised at its market value on its date of completion. The value assigned to completed new construction is known as a Proposition 13 base year value. If the January 1 lien date occurs while any new construction is in progress, that portion of the unfinished new construction in place on the lien date is also appraised at its value as of that date. However, unfinished new construction assessments are not base year values; rather, they are 'temporary' assessments until the new construction is completed.

Most repair, replacement, and maintenance are normally not considered to be new construction under the law and are generally not subject to assessment. However, any new construction that rehabilitates a structure (or a portion of a structure) to the substantial equivalent of a new structure is subject to assessment for tax purposes, even if much of the construction includes repair and replacement. New construction that changes the manner in which a property is used is also subject to assessment (for example: a residence converted to a multi-unit apartment).

The Assessor's Office discovers most new construction through building permits issued by the County and any of its cities. The Office then independently determines the value of the new construction and adds it to the assessed value of the existing property.

Questions about the assessment of new construction? Call (916) 875-0700 (9am to 4pm), or fax (916) 875-0705.