California does not offer a blanket sales tax exemption for residential solar. What exists instead is a construction contract tax structure that lowers the sales tax built into a contractor-installed system, a genuine partial sales tax exemption limited to qualifying businesses, and a property tax exclusion that keeps a solar installation from raising your home’s assessed value. Each works differently, and only some of them require anything from you.
Why Contractor-Installed Systems Carry Less Sales Tax
Most residential solar is installed by a contractor who supplies the equipment and does the work under a single contract. California treats that arrangement as a construction contract, which changes how sales tax is calculated and who pays it. The California Department of Tax and Fee Administration splits every solar installation into two component categories, materials and fixtures, and each is taxed differently.1California Department of Tax and Fee Administration. Tax Guide for Green Technology – Solar
For materials, the contractor is treated as the consumer and pays sales or use tax on their own wholesale cost. For fixtures, the contractor is treated as a retailer and owes tax on the selling price; in a lump-sum contract where fixture prices are not broken out, the taxable amount defaults to the contractor’s cost.2California Department of Tax and Fee Administration. Regulation 1521 – Construction Contractors
You never see a sales tax line on your invoice. The tax is embedded in the contract price, and because it is calculated on the contractor’s cost rather than a marked-up retail price, the total tax burden is lower than it would be on an equivalent retail purchase. That is where most of the talk about solar being “tax exempt” in California comes from. The system is not exempt. The tax base is just smaller, and it is hidden inside the contract.
Which parts of your system fall into which bucket depends on how the equipment attaches to the building. Rack-mounted panels on a roof, inverters, disconnect boxes, transformers, and batteries are fixtures. Wiring, mounting rails, brackets, and panels that actually replace a roof element (such as PV roofing tiles or a PV skylight) are materials.2California Department of Tax and Fee Administration. Regulation 1521 – Construction Contractors For a typical rooftop installation you don’t need to track any of this. The contractor handles the reporting under their seller’s permit, and the construction contract treatment applies automatically.
One thing worth asking your installer is whether the contract is lump-sum or time-and-materials, because fixture tax applies to the contractor’s cost in the first case and to a stated selling price in the second.1California Department of Tax and Fee Administration. Tax Guide for Green Technology – Solar
What Happens if You Buy the Equipment Yourself
If you buy panels and other components at retail and hire someone separately to install them, the construction contract framework does not apply. You are making an ordinary retail purchase, and the retailer charges sales tax on the full purchase price. Labor to attach panels you already own is not taxable, but the equipment is.2California Department of Tax and Fee Administration. Regulation 1521 – Construction Contractors
The cost difference is real. On a $25,000 system in a county with an 8% combined sales tax rate, paying tax on the full retail price rather than the contractor’s cost on materials can add several hundred dollars to the tax bill.
The Partial Exemption That Does Not Apply to Homeowners
California does offer a genuine partial sales tax exemption on solar equipment, but it is written for businesses. Under Revenue and Taxation Code Section 6377.1, companies primarily engaged in electric power generation, manufacturing, or certain research activities can claim an exemption from the state portion of sales tax on equipment used to generate electricity from non-conventional sources, including solar.3California Department of Tax and Fee Administration. Sales and Use Tax Law – Section 6377.1
Qualifying purchasers must fall within specified industry classification codes. The exemption covers only the state portion of sales tax, so local and district taxes still apply, and it is capped at $200 million in qualifying purchases per qualified person each year. Contractors buying qualifying equipment on behalf of a qualified person can also use the exemption.3California Department of Tax and Fee Administration. Sales and Use Tax Law – Section 6377.1
None of this reaches a residential installation on your own house. If you are a homeowner, Section 6377.1 is not available to you.
The Property Tax Exclusion That Does Apply to Homeowners
The tax benefit that actually reaches residential solar is a property tax exclusion rather than a sales tax one. Under Revenue and Taxation Code Section 73, adding an active solar energy system to your property does not count as “newly constructed” for reassessment purposes. Your county assessor will not raise your property’s assessed value because you installed panels, so your property tax bill does not go up after installation.4California Legislative Information. California Revenue and Taxation Code 73
An active solar energy system for this purpose includes equipment that collects, stores, or distributes solar energy for electricity, water heating, space conditioning, or process heat. Solar pool and hot tub heaters are specifically excluded. Storage devices, power conditioning equipment, and transfer equipment all qualify, up to the point where the electricity is conveyed or used. Components that serve both solar and non-solar functions qualify at 75% of their value.4California Legislative Information. California Revenue and Taxation Code 73
Watch the timing. Section 73 applies to lien dates through the 2025–26 fiscal year and is set to expire on January 1, 2027. The Legislature has renewed the exclusion in the past, but as of this writing a system installed in 2026 may not be covered in later assessment years unless the exclusion is extended again. The exclusion also ends when the property changes hands. You do not need to file anything to claim it; your assessor applies it automatically.4California Legislative Information. California Revenue and Taxation Code 73
The Federal Credit Is Gone in 2026
If you are weighing the full tax picture, this is the biggest change for 2026. The federal residential clean energy credit under Section 25D of the Internal Revenue Code, which gave homeowners a 30% credit on the cost of residential solar, no longer applies to systems installed after December 31, 2025.5Office of the Law Revision Counsel. 26 USC 25D – Residential Clean Energy Credit
The Inflation Reduction Act had carried the credit through 2032, but legislation passed in July 2025 moved the termination date to the end of 2025. For a 2026 residential installation there is no federal tax credit. On a typical system that is roughly $7,500 to $10,000 in lost tax savings. Leased systems and power purchase agreements run on the commercial version of the credit, which the solar company claims rather than you, and those arrangements may still carry some indirect benefit on systems that began construction before July 2026.
Records to Keep
California requires sales and use tax records to be preserved for at least four years, which applies to contractors and to any business claiming the Section 6377.1 partial exemption.6California Department of Tax and Fee Administration. Regulation 1698 – Records
As a homeowner, keep your installation contract, invoices, and any documentation showing how tax was calculated for the same four-year window. If the CDTFA audits your contractor and questions the tax treatment of your job, your own copies protect you from any downstream claim. Required records include the original contract, purchase receipts, bills, invoices, and any working papers tied to the tax treatment of the transaction.6California Department of Tax and Fee Administration. Regulation 1698 – Records
For the property tax exclusion, hold on to proof of the installation date and the system specifications. If your assessor ever questions whether Section 73 applies, documentation that the system qualifies and the date it was placed in service will resolve the question quickly.