The short answer
- Adding solar in California doesn't raise your property's assessed value, thanks to the active solar energy system exclusion (Revenue and Taxation Code §73).
- It ends for systems completed after Dec 31, 2026. A system finished on or before that day can qualify; one finished in 2027 can't (BOE).
- Systems that qualify keep the exclusion until the home changes owner (SB 710, 2025).
- Batteries that are part of a solar system are covered.
What the exclusion does
Normally, new construction is added to your assessed value. §73 says adding an "active solar energy system" isn't new construction, so it isn't assessed. A solar electric system "includes storage devices, power conditioning equipment, transfer equipment, and parts", so a battery installed with solar is covered too. The statute doesn't separately address a battery installed on its own.
The deadline
§73 "shall remain in effect only until January 1, 2027." The Board of Equalization told assessors that any system completed on any day before Jan 1, 2027 may qualify, and that construction still in progress on Jan 1, 2027 is assessable (Letter To Assessors 2024/031; BOE program page).
A 2026 bill to extend the exclusion to 2032, AB 2389, was held in committee on May 14, 2026.
If you already have solar
SB 710 (2025) added §73(i)(2): systems that qualified before Jan 1, 2027 stay excluded until the property changes ownership.
What it means for you
- If you're going solar anyway, finishing in 2026 avoids a reassessment of the system's value.
- "Completed" is what counts: allow for permits and inspections, and ask your installer for a written completion schedule.
- Your county assessor makes the final call. LA, Orange, San Diego, Riverside, San Bernardino and Ventura County assessors each handle the claim forms.
Not tax advice.
Checked against official sources on Oct 1, 2026. Sources are linked in the text. Not legal, tax or financial advice.