How much does ADU electrical work cost?
Electrical work for an accessory dwelling unit typically costs $1,500 to $8,000 in SoCal, an estimate for the subpanel, feeder and circuits. A separate utility meter costs more and is quoted apart.
Typical SoCal range, October 2026
$1,500 to $8,000
subpanel, feeder, circuits; a separate meter costs more. This is a desk estimate, not a quote.
This is an estimate. No published price table was read for the full range, so use it to judge whether a quote is in the right area. The typical SoCal range is $1,500 to $8,000 as of October 2026, for the subpanel, feeder and circuits. A separate meter costs more and is not in that range.
How an ADU gets power, by subpanel or separate meter, is on the ADU and remodel electrical page.
One anchor point does exist: Fixr’s national guide says a subpanel costs about as much as a standard panel installation, with a 100-amp panel at $1,200 to $1,800 and a 200-amp panel at $1,800 to $4,500, labor included. That is the panel part only, without the feeder run, circuits or heavier loads that an ADU brings.
What the electrical scope includes
- A subpanel in the ADU, sized to its loads
- A feeder from the main panel or service to the subpanel
- Branch circuits for lighting, outlets, appliances and any dedicated loads
- Smoke and carbon monoxide detectors, as the building code requires for a dwelling
- The permit and inspections
An ADU is a full dwelling in the eyes of the code. It needs a kitchen and bath circuits, GFCI protection where required and a smoke alarm layout, not just a few outlets. See the subpanel cost page for the main part.
Why the range is wide
Distance. The feeder is the biggest swing. A garage conversion beside the main panel needs a short run. A detached unit at the back of a lot needs a trench or overhead span.
Loads. An ADU with a gas range and gas water heater needs less capacity than one with an induction range, heat pump and EV charger. Heat pump circuits are one common item.
Main panel. The ADU shares the service unless a new one is built. If the house has a 100 amp panel, the extra load may need a panel upgrade first. A load calculation, explained in the load calculation guide, tells you where you stand.
Separate meter versus shared
A separate meter lets the ADU have its own bill. It means working with the utility, and the equipment and fees differ by utility and city. That is why it is excluded here. Ask your utility early, and see the ADU electrical requirements guide for what the plan review is likely to ask.
Permits and fees
ADU electrical goes through the city’s building permit and plan review. Under California law, ADU approvals are governed by Government Code section 66314 and nearby sections, and your city adds its own checklist. Fees vary widely. Look at the page for your city, such as Los Angeles or San Diego, and start with the permits guide.
Plan the electrical early
Electrical is the trade most often left to the end of an ADU design, and it causes the most change orders. Decide early where the subpanel goes, which appliances are electric, and whether the unit gets its own meter. Those three choices set the feeder size, the trench route and the main panel question. An electrician who sees the plans before they are final can flag a feeder that is too small or a panel location that blocks code clearances, and that saves money compared with changing it after framing.
How to compare quotes
- Ask for the load calculation behind the subpanel size.
- Ask what feeder size and length the quote assumes.
- Ask whether trenching, conduit and surface repair are in the price.
- Ask whether plan-check drawings are included.
- Ask what changes if the main panel needs an upgrade. Use the quote checklist.
What is not included
- A separate utility meter and any utility charges
- A main panel or service upgrade
- Appliances, heat pumps and EV chargers
- Excavation, concrete and landscape repair
- Architectural plans and engineering
What moves the price
| Factor | Effect |
|---|---|
| Subpanel and feeder from the main house | A longer feeder, trenching or an overhead run raises cost; a garage conversion next to the main panel sits at the low end |
| Size of the ADU and its loads | Electric cooking, a heat pump, a water heater and an EV charger all add load and may push the feeder size up |
| Main panel capacity | If the main service cannot carry the ADU, a panel or service upgrade comes first |
| Separate meter or shared meter | A separate meter means utility coordination and added equipment; the estimate for this page does not include it |
| New build or conversion | A new structure gets wiring while open; a conversion of an old garage may need old wiring brought up to code |
Questions people ask
Can an ADU share the main house's electrical panel?
It can share the service, usually through a subpanel fed from the main panel, as long as the service can carry the added load. Whether the ADU gets its own meter is a separate decision with the utility, and rules differ by utility. A load calculation settles whether the existing service is enough.
Does an ADU need its own electric meter?
Not always. Many ADUs run off a subpanel and the main meter. Some owners want a separate meter to bill a tenant. That involves the utility and extra equipment. Ask your city and utility, and see the ADU requirements guide, before you design the electrical system.
Why is the ADU range so wide?
The scope varies more than the labor. A small conversion with a short feeder is a modest job. A detached unit with a trench, a new panel, electric appliances and a heat pump is a large one. This range is a desk estimate, so use real quotes after a load calculation.
Do ADU electrical plans need review?
ADUs go through the city's building plan process, and the electrical plan is part of the package. Many cities want a single-line diagram or load calculation. Ask the city for its ADU submittal checklist, and have your electrician review it before the drawings are finalized.
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Pick your panel, target size and site conditions to get a typical SoCal range.
$1,500 to $8,000
subpanel, feeder, circuits; a separate meter costs more.
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