Subpanel Installation
Subpanel installation for garages, workshops, and additions — licensed electricians, load assessment and permits included.
Schedule Your Service
- ★★★★★ 5.0
- ✓ Licensed & Insured
- ⚡ Same-Day
A subpanel extends electrical service from the main panel to a remote location without running every circuit all the way back to the main panel. Subpanels are commonly installed in detached garages, workshops, pool houses, large additions, and commercial spaces requiring multiple circuits at a distance from the main panel. Our licensed electricians size subpanels correctly for the intended load, run appropriately sized feeder cable, coordinate any required utility service upgrades, and file permits with the local building authority. Every subpanel installation is inspected before the job is considered complete.
Subpanel Installation — Everything You Need to Know
From sizing and placement to permits and load calculations — here’s what homeowners need to know about subpanel installation before requesting service.
What Subpanel Installation Involves
Subpanel installation begins with a load calculation for the space being served — the total amperage of all planned circuits determines the subpanel and feeder cable size. We assess the main panel for available capacity to supply the feeder circuit. If the main panel is at or near capacity, an upgrade may be required before the subpanel can be installed safely. We run feeder cable from the main panel to the subpanel location, install the subpanel with the required main breaker, and wire the branch circuits serving the space.
Common Subpanel Applications
Detached garages being converted to workshops or living spaces are the most common subpanel project — a garage addition typically requires six to twelve circuits for lighting, outlets, dedicated tool circuits, and EV charging. Pool houses and guest cottages at a distance from the main house require subpanels rather than long individual circuit runs. Large home additions with multiple rooms and appliances are better served by a subpanel than by running all circuits back to a crowded main panel.
Sizing and Capacity Check
Correct subpanel sizing depends on the total planned electrical load of the served space, not just the number of circuits.
- Load calculation before sizing
- Main panel capacity assessed first
- Feeder cable sized to rating
- Permits filed
Why Correct Sizing Matters
An undersized subpanel limits circuits and may require replacement when loads increase. An oversized feeder without matching main panel capacity overloads the main panel. We calculate both sides — subpanel load and main panel capacity — before specifying any equipment, so the installation is correctly sized from day one.
- Both load and capacity calculated
- Feeder cable correctly rated
- Permits and inspection included
- Fixed quote before install
- Same-day service available
Subpanel installation across 54 cities in California and New Jersey. Find your city below.
What Our Customers Say About Subpanel Installation
Here’s what homeowners say about our subpanel installation service. Every review is from a verified customer in Southern California.
★★★★★
“We needed a 200-amp panel upgrade before installing our EV charger. The electrician handled the utility paperwork, pulled the permit, and finished the job in one day. Passed inspection on the first visit.”
Michael R.
Anaheim, CA
✓ Google Review
★★★★★
“Our 1965 Federal Pacific panel was flagged by our insurance company. Got three quotes and chose Local Trusted Electricians because they fully explained the scope before asking for a deposit. Permits handled, clean work.”
Sandra K.
Long Beach, CA
✓ Google Review
★★★★★
“Added a home addition and needed more panel capacity. They ran a proper load calculation, recommended the right amperage, and delivered the upgrade on schedule and on the quoted price.”
David H.
Orange County, CA
✓ Google Review
Our Electrical Services in Anaheim
Helpful electrical guides, safety tips, and local service advice for Anaheim homeowners.
When to Replace a Circuit Breaker in an Older La Habra Home
Knowing when to replace a circuit breaker is not always obvious, especially in a city like La Habra, where more
Request a Subpanel Installation Quote
Correctly sized from day one — permits and inspection included.