Which permit
From the Community Development Agency's How to apply for a building permit page (read 26 October 2026), under "Minor improvement permit online": "We review your plans at the job site. You receive your permit online up front. You don't have to send your plans to us."
| Job | Permit in unincorporated Marin |
|---|---|
| Residential rooftop photovoltaic | Minor improvement permit, online |
| Energy storage system (battery) | Minor improvement permit, online |
| Backup generator | Minor improvement permit, online |
| Panel upgrade or EV charger on its own | Electrical maintenance permit, online, no plans |
| Ground-mounted array, or solar on an addition | Not on the minor improvement list; ask Building and Safety, 415-473-6550 |
The County permits only the unincorporated area. San Rafael, Novato, Mill Valley, Sausalito and Marin's other cities and towns issue their own solar permits, which are not in the County portal or our file.
How to apply and close it
- Start in the County permit portal, which handles every building permit, and choose the minor improvement permit.
- Pay online. The County says it will never ask for payment by wire, Zelle, Venmo or PayPal.
- Keep the drawings on site. Because the plans are reviewed at the job site, the inspector checks the installed system against them; the job card is posted and the inspection card signed at each visit (How permits work).
- Pass the final inspection, and get a copy of the signed card. A permit expires in one year, and each passed inspection extends it a year.
What it costs
The County's Fee Explanation page (read 26 October 2026) lists the lines on every permit bill; none mentions solar or an exemption for it:
| Line | How it is calculated |
|---|---|
| Building permit application fee + issuance fee | 77% and 23% of the Building and Safety service fee |
| Planning surcharge | 10% of those two fees |
| Technology enhancement fee | 6% of those two fees |
| Seismic (SMIP) tax | 0.01% of job value for residential, 50-cent minimum |
| Building Standards "green" tax | 0.004% of job value, $1 minimum |
| Roads impact fee | 1% of job value, on improvements of $10,000 or more |
The roads line matters more for solar than for most trades: the usual system is filed at $29,222, so 1% is about $290 before the service fee itself, and a solar-plus-battery job at $40,000 is $400. The page lists no exemption, but it also does not say the line is charged on minor improvement permits; the portal invoice is the final word. The base service fee is on a separate schedule in the portal.
Who should install it
CSLB lists a "C-46 - Solar Contractor" classification and "C-10 - Electrical Contractor" (CSLB classifications). Marin permits carry the license number typed in by the applicant; look it up on Check A License and match the name to your contract. 84.4% of solar firms in our file matched an active CSLB license; 4 matched a license with a problem status.
What 1,339 Marin County solar permits show
| Measure | Unincorporated Marin solar and battery |
|---|---|
| Permits on homes, October 2023 to September 2026 | 1,339 |
| Installers | 199 |
| Installers with a permit in the last 12 months | 70 |
| Usual filed value | $29,222 |
| Middle half of installers' usual value (71 firms) | $17,952 to $38,536 |
| Busiest installer / its permits in the last 12 months | Sunrun Installation Services Inc / 21 |
| Share held by the five busiest | 37.6% |
| Installers with one permit only | 92 (46.2%) |
| Installers with 5+ permits, none in the last 12 months | 13 |
| Busiest / quietest month | October (182) / June (69) |
Solar filing in unincorporated Marin is lumpy: October runs at 182 on our seasonal index against 69 in June. The middle half of installers usually file between $17,952 and $38,536, so ask whether a quote includes a battery before comparing. 13 installers with five or more permits filed none in the last year of the data; check that an installer is still pulling permits. Prices by home value: Marin County solar cost; counts by year: Marin County permit statistics.
See every Marin County solar installer by permits filed →
Before you hire
Check the license with the Marin County contractor license lookup and compare installers on the Marin County solar list. Panel upgrades and EV chargers: Marin County electrical permit. Rules elsewhere: do I need a permit for solar panels; national prices: solar panel installation cost; questions to ask: hiring a solar installer.
What this does not tell you
Minor improvement permits never appear in the County's inspection file, so we cannot say how many solar permits passed final or how long they took. Our data covers only unincorporated Marin. Filed values are the installer's figure. Our license match uses the number on the permit or the business name, so a mismatch is a reason to check, not a finding.
How we know this
The permit type and process are quoted from the Marin County Community Development Agency's How to apply for a building permit page and the fee lines from its Fee Explanation page, both read 26 October 2026; permit life from its How permits work page, read 23 October 2026; license classes from CSLB's classifications page, read 26 October 2026. Fee examples are our arithmetic. Permit counts are Marin County building permits for solar and battery work on homes in unincorporated Marin, October 2023 to September 2026; license status is our match to the CSLB license master file.
Numbers come from Marin County Community Development Agency building permits on homes in unincorporated Marin (the County's open-data permit and inspection files), data through October 19, 2026. Nobody paid to be on this page and nobody can.
Questions
- Do I need a permit for solar panels in Marin County?
Yes. In unincorporated Marin, residential rooftop photovoltaic systems and energy storage systems go on a minor improvement permit, issued online up front with the plans reviewed at the job site. Homes inside San Rafael, Novato, Mill Valley and Marin's other cities and towns get their permits from the town, not the County.
- How long does a solar permit take in Marin County?
The County says a minor improvement permit is issued online 'as quickly as you can complete the application'. Projects that need plans submitted first, such as additions, take 6 to 8 weeks by the County's estimate.
- How much is a solar permit in Marin County?
The bill is the Building and Safety service fee plus a 10% planning surcharge, a 6% technology fee, state taxes of 0.01% and 0.004% of job value, and a roads impact fee of 1% of value on improvements of $10,000 or more. On a $29,000 system that 1% line alone is $290.
- Do I need a permit for a home battery in Marin County?
Yes. The County lists energy storage systems with rooftop solar and backup generators as minor improvement permits, applied for online and inspected at the job site.
- What license does a solar installer need in California?
CSLB lists a C-46 Solar Contractor classification; electricians hold C-10. Marin permits carry the installer's license number, so match it to your contract on CSLB's Check A License.
Build your own list
Every firm with that kind of permit on record. Pick what you value. The list moves.
Related guides
- Albuquerque building permit search: how to look up permits on an address
- Do I need a solar permit in Albuquerque? Building and electrical permits, the engineer triggers and the fee
- Do I need a solar permit in Anaheim? The online small-rooftop permit, the 10 kW line and the City utility
- Do I need a solar permit in Bend, OR? The prescriptive checklist, the 2026-27 fees and how fast permits final
- Do I need a solar permit in Pittsburgh? The electrical permit's PV scopes, the $130 minimum fee and who can pull it
- Do I need a solar permit in Sacramento County? SolarAPP+, the EC-23 plan set, and how fast installers close
For one city
- How to apply for a building permit — Marin County Community Development Agency (accessed 2026-10-26)
- Building Permits: Fee Explanation — Marin County Community Development Agency (accessed 2026-10-26)
- How permits work — Marin County Community Development Agency (accessed 2026-10-23)
- CSLB Licensing Classifications (accessed 2026-10-26)
- Check A License — CSLB (2026-10-23)