What a cleaning visit covers and who may do it
A cleaning visit washes the face of the panels, priced either for the whole system or panel by panel. The model in the cost table prices both ways, so a quote should say which it is. CSLB's Solar Smart page describes the C-46 Solar class as covering work to install, modify, maintain and repair photovoltaic systems, and names A, B, C-10 and C-46 as the classes that can legally install them.
CSLB's no-exam page says a contractor license is required when a project needs a building permit, uses employee labor, or totals $1,000 or more across its contracts, and a larger project can't be split into pieces under $1,000. Since January 1, 2025 (AB 2622), an unlicensed person advertising work under that line must say they're not licensed. Ask the company which side of the line its job falls on, check any license number on CSLB's lookup, and ask who exactly will be on your roof.
California cleaning prices, per visit and per panel
Our model puts a whole-system cleaning at $140 to $630 per cleaning visit, whole system, and the table adds a per-panel row. It takes one national range, widens it 15 percent each side and applies the wage ratio of 1.09 for California installers. No permit fee is in it and no federal credit is subtracted, so treat it as an estimate and not a quote.
The ranges don't cover roof repair, panel replacement, a recurring plan or any production result. Ask whether the price is for one visit or a year of visits.
| Item | Figure | What it is |
|---|---|---|
| Estimated range, not a quote | $140 to $630 per cleaning visit, whole system | Built from one national published range, adjusted by the California solar installer wage ratio (1.09). Before any incentive: there is no federal credit for a system installed in 2026. Basis: no California company price for this job, so the national estimate stands. |
| Estimated range per panel, not a quote | $15 to $30 per panel cleaned | Built from 2 national published ranges, adjusted by the California solar installer wage ratio (1.09). Before any incentive: there is no federal credit for a system installed in 2026. Basis: no California company price for this job, so the national estimate stands. |
| Solar photovoltaic installer wage, California mean | $30.42 an hour | BLS OEWS, May 2025: the pay of installers, which is not what a cleaning company charges. |
Estimated range. Built from national published ranges (1 source), adjusted by California's solar installer wage ratio to the US (1.09, BLS May 2025), plus the city solar permit fee where the city publishes one. Not a quote. One California installer publishes its own quoted range (per watt and per battery), too few to build a range from; the others print blog averages, which we do not count. We have no California company price for this job, so the range is our national estimate alone. Full method. Prices as of Oct 23, 2026.
Your app and your bill: the evidence to bring
Your own records are the evidence here. NREL's O&M best-practices guide doesn't set a cleaning interval, so the monitoring app's output history and the exports line on your utility bill are what to bring to a cleaning company or your installer.
Under net billing in PG&E, SCE and SDG&E territory, the CPUC credits exports at hourly Avoided Cost Calculator values, usually lower than import rates, and NBT bills arrive monthly. Read the app and the bill side by side and write down the dates of any drop.
Don't take a production promise on faith. Solar Smart tells buyers to get savings and production claims in writing, and a cleaning pitch that names an output gain is one of those claims.
The cleaning method to ask about, and the water rules
NREL's O&M best-practices guide (2018 edition, written mainly for utility-scale and commercial systems) says "Soiling reduces the energy output of the PV array and can lead to localized hot-spot failures if the soiling is uneven." It tells crews to follow the module maker's recommendations and clean with plain demineralized water and a mild detergent the maker recommends, and it calls a bucket, strip cleaner and squeegee with overlapping vertical strokes an economical method. Its warning is plain: "Do not use high-pressure water, brushes, or any types of solvents, abrasives, or harsh detergents." Ask the company what it uses.
Two water agencies print outdoor rules a hose crew works under, though neither names solar panels. LADWP's conservation ordinance page, written for irrigation, hard surfaces and vehicles, put Los Angeles in Phase 2 on October 23, 2026. It bans runoff onto streets, driveways and gutters and all outdoor watering from 9:00 a.m. to 4:00 p.m., with fines of $100 to $600 after a written warning. San Diego's permanent restrictions require a power washer or a hose with a shutoff nozzle for washing paved areas, with the water kept out of the storm sewer. In either city, ask the crew where its water goes.
The roof, the warranty and who's responsible for upkeep
Nothing on this page asks you to climb onto the roof or hose down the array yourself, and Cal/OSHA's rules show why roof work belongs to a crew. Its construction orders, 8 CCR 1670(a), require fall arrest, restraint or positioning systems for employees exposed to falls of more than 7 1/2 feet, including on sloped roofs steeper than 7:12. Its general industry orders, 8 CCR 3212(d), call for guardrails where employees routinely work within 6 feet of a roof edge, "routine" meaning more than four times a year. Which set covers a cleaning crew is for Cal/OSHA to say.
Ask the company what fall protection its workers use, whether the method and products are allowed under the panel and roof warranties, who is responsible if something is damaged, and whether the price covers one trip or several.
If your system is leased or on a power purchase agreement, you don't own it, and CSLB's supporting-information form asks whether the deal is a lease or PPA. Check that contract for who is responsible for upkeep before you pay anyone to clean. If you bought it, Solar Smart's list of the downsides of buying outright includes this line: "You're responsible for the system maintenance and all repairs."
Solar Smart's payment advice for solar buyers, to keep control of payments to the contractor, fits a cleaning contract too: pay for a visit once it's done, and keep the receipt with the warranty papers.
Comparing a per-visit quote with a per-panel one
The table shows a whole-system visit and a per-panel row. Multiply a per-panel quote by your panel count, or divide a per-visit quote by it, to compare the two on the same footing, and ask whether a minimum charge applies to a small system. A company that bundles cleaning with an inspection should price each part, and the system inspection page has that visit's estimate.
When something on the roof can't wait
- Smoke or fire at the panels, wiring or inverter, or a burning smell on the roof: call 911 and keep away from it.
- Output is lower than you expected.
- The monitoring app is offline.
- A panel looks dirty or stained from the ground.
What to note from the ground and the app
- Open the monitoring app and screenshot the output history for the last few months.
- Read the exports line on your latest utility bill.
- Look at the panels from the ground and note anything you can see, without going on the roof.
Does cleaning need a permit
Our cost model adds no permit fee for a washing visit. If a company proposes to change or move equipment while it's on the roof, that's a different job, and the solar repair page covers the permit and utility questions that come with it.
Ask for the company's contractor license number and look it up with your state's licensing board before you sign.
Questions people ask
How often should solar panels be cleaned in California?
Start from your monitoring app's output history and your bill. Bring both to an installer or cleaning company, with the dates, so the advice rests on your own system's numbers.
Do I need a license to clean solar panels?
CSLB's no-exam page draws the license line at a building permit, employee labor, or a project total of $1,000 or more. Ask the company which applies to its job, and check any license number it gives you on CSLB's lookup or at 800-321-CSLB (2752).
Should I clean the panels myself?
We don't ask you to get on the roof. Cal/OSHA requires fall protection for employees working near roof edges, so ask a company who will be up there, what fall protection it uses and what its method does to the panel warranty.
Does cleaning increase production?
We don't print an output gain. Solar Smart says to get any production claim in writing, so ask the company to put its figure on the quote.
How much does solar panel cleaning cost in California?
Expect $140 to $630 per cleaning visit, whole system from our model, an estimate and not a quote. A per-panel row sits in the table for quotes priced that way.
- U.S. Bureau of Labor Statistics, OEWS May 2025: Solar photovoltaic installers (SOC 47-2231), California statewide, mean hourly wage Read Oct 23, 2026.
- U.S. Bureau of Labor Statistics, OEWS May 2025: Solar photovoltaic installers (SOC 47-2231), United States (national), mean hourly wage Read Oct 23, 2026.
- SolarPanelMatch: how we estimate costs, California (editorial policy) Read Oct 23, 2026.
- BLS Public Data API (OEWS series OEUS060000000000047223101..13, OEUN000000000000047223101..13) Read Oct 23, 2026.
- CSLB Solar Smart Read Oct 23, 2026.
- CSLB Licensing Classifications Read Oct 23, 2026.
- CSLB Solar Energy System Disclosure Document (13L-6) Read Oct 23, 2026.
- CSLB Solar Energy System Supporting Information Read Oct 23, 2026.
- CPUC Net Energy Metering and Net Billing Read Oct 23, 2026.
- NREL, O&M Best Practices for Photovoltaic and Energy Storage Systems, 3rd ed. (Wayback copy 2026-01-19) Read Oct 23, 2026. Confirm with the source before you rely on it.
- Cal. Code Regs., tit. 8, section 1670 (DIR) Read Oct 23, 2026.
- Cal. Code Regs., tit. 8, section 3212 (DIR) Read Oct 23, 2026.
- CSLB, Before Applying for a License When No Exam is Required Read Oct 23, 2026.
- CSLB press release, AB 2622 (2024) Read Oct 23, 2026.
- LADWP, Water Conservation Ordinance Read Oct 23, 2026.
- City of San Diego, Water Use Restrictions Read Oct 23, 2026.