Electrical panel upgrades in Southern California: when and how

What the panel does

The panel is the box where power from the utility splits into the circuits in your house. It holds the main breaker, which can shut off the whole house, and a breaker for each circuit. Its size in amps sets how much your home can draw at one time. A panel can be full in two ways. It can be full by slots, with no empty spaces for new breakers. It can also be full by load, when everything on it adds up to the limit of the service.

Who needs an upgrade

Most upgrades fall into one of four groups.

• The panel is old or a known problem brand. Many electricians recommend replacing Zinsco and Federal Pacific panels. A federal review of Federal Pacific breakers in 1983 found failures in some lab tests but ordered no recall, and for Zinsco the concerns come from trade sources, so ask an electrician to look at yours. See Zinsco and Federal Pacific panels.
• The home is adding a big load. An EV charger, heat pump, induction range, hot tub or ADU often pushes a 100 amp service past its limit. The load calculation guide shows how that is worked out.
• The panel has no room. Tandem breakers and stacked circuits are a sign that the box has run out of space.
• A buyer, insurer or inspector flagged it. Some home sales stall over the panel.

If you only need a few extra circuits and the service has room, a subpanel may be cheaper than a full swap.

The decision points

Size. Most houses go to 200 amps. The details are in 200 amp panel upgrades. Larger homes or all-electric homes with several big loads may need 400 amp service.

Where the meter and mast are. If the meter stays put, the job is a swap. If the old service entrance, mast or meter socket cannot take the new panel, or the meter has to move, the job grows. Meter and service mast work is where most cost surprises come from.

Standard or smart panel. A smart electrical panel monitors circuits and can limit total load. It costs more than a standard panel, and it only helps if your inspector and utility accept it.

Surge protection. The 2023 National Electrical Code, which California’s 2025 code is based on, requires a surge protective device at new and replaced dwelling services, so one is part of the job. See whole-home surge protection.

Breaker box replacement and electrical panel replacement

Breaker box replacement and electrical panel replacement describe the same job as a panel upgrade: the old panel and its breakers come out and a new panel goes in. People say upgrade when the amperage goes up and replacement when the size stays the same, as with a Zinsco or Federal Pacific panel or a box with rust or burn marks. Both need an electrical permit and a city inspection, and the permit and inspection page walks through the steps. The breaker box replacement cost page covers the price.

What it costs

The typical SoCal range for a 100 to 200 amp swap in place, with permit, is $2,500 to $4,500 as of October 2026. Jobs with a new service run, a meter or mast move, trenching or stucco repair are a different class, at about $5,500 to $10,000. The panel upgrade cost page lists what pushes a quote up, and the cost estimator gives a first number.

Three parties, one job

A panel swap involves the electrician, the city building department and the utility. The order matters.

1. The electrician contacts the utility service planner. At least one city in the area, Laguna Niguel, asks for a copy of the utility service order before it issues the permit.
2. The electrician pulls the permit and schedules the utility disconnect.
3. The utility cuts power, the electrician swaps the panel, and the city inspects it. Some city procedure sheets describe a morning disconnect and an afternoon reconnect once the inspection passes, but timing is not guaranteed and differs by utility.
4. The city releases the meter, and the utility reconnects power.

Cities differ, and your city’s checklist wins. The permit and inspection page walks through each step, and the utility coordination guide covers SCE, SDG&E and LADWP differences.

Code in force

California’s 2025 Electrical Code took effect January 1, 2026. It is based on the 2023 National Electrical Code. A new panel is installed to that code, and the installer should confirm with the city which edition it enforces for permits.

A new or replaced panel also triggers the surge protection rule, and the surge protector cost page shows what the device costs.

Before the electrician comes

Take a photo of the panel with the door open, find the main breaker size, and note where the meter sits. Those three items let an electrician give a useful first answer. The guide to reading your panel shows what to look for. Send a photo of your panel.