Subpanel Installation Cost in 2026
Last updated: September 2026
Subpanel cost depends heavily on amperage — a 50A subpanel for a workshop and a 200A subpanel for a detached structure are very different projects. Here's the reference range for each, when a subpanel makes sense, and a free calculator to check your own quote.
50–60A
$400–$600
100–125A
$500–$1,500
150A
$600–$1,800
200A
$800–$2,000
Estimated national reference range: This is an estimated national reference range based on early (V1) research — not a guaranteed local price. Actual costs depend on your specific project and location.
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What Is a Subpanel, and When Do You Need One?
A subpanel is a secondary distribution point, fed from your main panel, that hosts its own set of breakers. It's the typical solution when you're extending power to a garage, workshop, addition, or accessory dwelling unit (ADU) — or when your main panel is simply out of open breaker slots for new circuits.
Subpanel vs. a dedicated circuit
If you only need power for one appliance or piece of equipment, a single dedicated circuit is usually simpler and cheaper. A subpanel makes more sense when you're adding several circuits at once. See our dedicated circuit guide for that comparison.
Subpanel vs. a full service upgrade
A subpanel adds capacity to one location without changing your home's overall electrical service. If your whole home is undersized, a service upgrade may be the more appropriate fix — see 200 amp panel upgrade vs. full service upgrade.
Choosing the Right Subpanel Amperage
50–60A subpanel
A small workshop, a handful of circuits, or a single large appliance like a hot tub.
100–125A subpanel
A garage, small ADU, or an addition with several circuits and general-purpose loads.
150A subpanel
A larger detached structure or a workshop with heavier equipment loads.
200A subpanel
A substantial detached structure, or a mix of heavy loads like an EV charger plus workshop tools.
This is general guidance, not a substitute for a licensed electrician's load calculation — the right amperage depends on exactly what you plan to run, now and in the future.
What Drives Cost
- Distance from the main panel
- The farther the subpanel is from the main panel, the more wire, conduit, and trenching (if underground) the run requires.
- Indoor vs. garage vs. detached structure
- An indoor subpanel near the main panel is typically the simplest install; a detached structure often means longer runs and more permitting.
- Number of circuits planned
- A subpanel sized for more future circuits may cost more upfront but avoid a second project later.
What to Ask Your Electrician
- What amperage subpanel are you recommending, and how did you size it?
- How far is the run from the main panel, and does that include trenching if it's underground?
- Is the permit fee included, or billed separately?
- How many breaker slots will the new subpanel have available for future circuits?
Your quote may vary because of permits, utility requirements, meter work, panel location, wiring condition, code upgrades, and project complexity. Being above this reference range does not necessarily mean the quote is overpriced.
Frequently asked questions
How much does it cost to install a subpanel?
Cost depends heavily on amperage. Our current national reference ranges are $400–$600 for 50–60A, $500–$1,500 for 100–125A, $600–$1,800 for 150A, and $800–$2,000 for 200A. These are estimated reference ranges, not guaranteed local prices.
How do I know what amperage subpanel I need?
It depends on what you're powering. A small workshop or a single large appliance often only needs 50–60A, while a garage or ADU with multiple circuits typically needs 100A or more. A licensed electrician can calculate your actual load based on what you plan to run.
Do I need a permit for a subpanel?
In most U.S. jurisdictions, yes — subpanel installation typically requires a permit and inspection, similar to main panel work.
Is a subpanel cheaper than a full service upgrade?
It depends on the goal. If you just need more breaker capacity for a garage, addition, or workshop, a subpanel is often the more targeted (and sometimes cheaper) option versus increasing your entire home's service. If your whole home is undersized for its electrical demand, a service upgrade may be the more appropriate fix. See our panel upgrade vs. service upgrade guide for that comparison.
Can a subpanel be installed outdoors or in a detached garage?
Yes — subpanels are commonly installed in garages, workshops, and other detached structures, using weatherproof-rated equipment when outdoors. This typically involves a longer wire run (and possibly trenching for underground service), which affects cost.
Methodology and Sources
National reference ranges for installing a new subpanel, by subpanel amperage.
This is an early-stage (V1) national reference point, not a hyper-local estimate. No ZIP-code or regional adjustment is applied yet.
Sources
- HomeGuide — Cost to Install a Subpanel
National reference ranges for installing a new subpanel, by subpanel amperage.
Last updated: September 2026