Most people wire a new garage for the car they have and the light switch by the door. Then they buy an electric car, a compressor or a welder, and find that the garage has one 20-amp circuit and the panel is full. Adding power to a finished garage means opening walls. Adding it while the framing is open costs a fraction of that.
This guide covers what a new garage needs electrically, what each part costs, and the decisions that are cheap now and expensive later. Detached garages get extra attention, because getting power to them is a project of its own.
Key takeaways
- Wiring a new garage costs $4 to $9 per square foot, about $2,000 to $4,500 for 500 sq ft (HomeGuide).
- A buried line to a detached garage runs $10 to $25 per linear foot; a subpanel adds $500 to $1,700.
- A Level 2 EV charger installation averages $967; panel upgrades, if needed, add $800 to $2,000 (HomeAdvisor).
- Even without an EV, run a circuit or conduit for one while the walls are open.
What a basic garage needs
HomeGuide describes basic garage electrical service as outlets, lighting and the circuit for the garage door opener. Most garages need at least one 20-amp circuit for tools and another dedicated circuit for the opener, and more complex setups with 240-volt service for heavy equipment cost more.[1] HomeGuide also notes that the National Electrical Code requires GFCI protection in garages and at least one outlet per car space, and puts GFCI outlets at $150 to $350 each installed.[2]
For new construction, HomeGuide prices garage and shop wiring at $4 to $9 per square foot, depending on location and the number of circuits. Open floor plans need fewer switches and outlets than the same area divided into rooms.[2]
| Garage or shop size | Wiring cost, new construction |
|---|---|
| 250 sq ft | $1,000 to $2,300 |
| 500 sq ft | $2,000 to $4,500 |
| 800 sq ft | $3,200 to $7,200 |
| 1,000 sq ft | $4,000 to $9,000 |
HomeAdvisor gives a similar figure for a detached garage: $1,000 to $3,800 for an electrician to wire the space, up to $5,000 for complex layouts.[3]
Getting power to a detached garage
An attached garage can usually be fed straight from the house panel. A detached garage needs a line run to it, and HomeGuide says most cities require that line to be buried. It prices an underground run at $10 to $25 per linear foot, not counting the wiring inside the building.[2]
| Distance from the house | Underground line | Overhead line |
|---|---|---|
| 50 ft | $500 to $1,250 | $250 to $350 |
| 100 ft | $1,000 to $2,500 | $500 to $700 |
| 150 ft | $1,500 to $3,800 | $750 to $2,300 |
| 200 ft | $2,000 to $5,000 | $1,000 to $3,000 |
A garage with more than one circuit needs a subpanel, which HomeGuide puts at $500 to $1,700. It also warns that homes with less than 200-amp service typically need a main panel upgrade before running power to a garage, at $1,400 to $2,800.[2] That is the cost people forget. Ask the electrician to check your main panel before you budget anything else.
Size the feed for what comes later
The trench is the expensive part of a line to a detached garage, not the wire. If there is any chance you will add an EV charger, a heater or a welder, ask for a feed and subpanel big enough for them now, or at least an oversized conduit you can pull new wire through. Digging the same trench twice is the costly way to do it.
Planning for an electric car
HomeAdvisor puts electric car charger installation at $554 to $1,380, $967 on average. A Level 1 charger plugs into a standard 120-volt outlet and adds three to five miles of range per hour. A Level 2 charger needs a 240-volt circuit and adds 12 to 80 miles per hour, enough to fill a depleted battery overnight. The Level 2 unit itself costs $700 to $2,000.[4]
The installation is where a new garage saves money. HomeAdvisor says a Level 2 charger needs a dedicated 50-amp (minimum) 208 to 240-volt circuit, and that adding a 240-volt circuit to an existing garage can mean $800 to $2,000 for a panel upgrade and $500 to $1,500 for rewiring. Permits add $100 to $200.[4] The Department of Energy's Alternative Fuels Data Center adds that permits and an approved site plan may be required, and that an electrician can tell you whether your home has enough capacity.[5]
HomeGuide puts a complete Level 2 setup, with the charger, a 240-volt outlet, wiring and wall mounting, at $750 to $2,600.[2] If you don't own an electric car yet, the cheap move is to run the circuit, or at least the conduit, to where the charger would go while the walls are open.
Workshop circuits and lighting
A garage that doubles as a workshop needs more than parking power. Plan outlets at bench height along the walls where you will work, on more than one circuit so two tools can run at once. Large stationary tools, air compressors and welders often need their own 240-volt circuits. HomeGuide notes that workshops needing climate control and heavy-duty tools may need more power than the home's panel can supply, and suggests upgrading the home's main service rather than adding a second meter, since some utilities bill a second meter at a higher commercial rate.[2]
Lighting is worth over-doing. A garage has no daylight spilling in from other rooms, and dim light makes detailed work hard and tripping easy. Put switched lighting at every door, and motion-sensing lights outside a detached garage and along the path to the house.
Heating and cooling
If you plan to heat or cool the garage, the electrical plan needs to know now. A ductless mini-split is the common choice for a garage because it heats and cools without ducts. HomeGuide puts a single-zone system at $2,500 to $6,000 installed.[6] It needs its own circuit, which is much easier to run during construction. A mini-split also only makes sense in an insulated garage, so plan insulation at the same time.
An electrical plan for a new garage
Before the electrician prices the job, decide on:
- where the cars will park, so outlets and an EV circuit land in the right place
- where a workbench will go, and which tools need 240 volts
- whether you will heat or cool the garage
- lighting inside, at each door and along the path to the house
- for a detached garage, the size of the feed and subpanel, with room to grow
- whether the main panel has the capacity, or needs an upgrade first
Our garage cost calculator prices wiring by floor area, adds the buried line for a detached garage by distance, and has options for a subpanel, a Level 2 EV charger and a mini-split. The research behind the calculator lists each source. For the house itself, see our guide to plumbing and electrical rough-in costs.
Set the distance from the house, add a subpanel, an EV charger or a mini-split, and see the full garage cost.
Frequently asked questions
How much does it cost to wire a new garage?
HomeGuide puts new-construction wiring at $4 to $9 per square foot, or $2,000 to $4,500 for a 500 sq ft garage. HomeAdvisor puts wiring a detached garage at $1,000 to $3,800.
How much does it cost to run power to a detached garage?
HomeGuide puts a buried line at $10 to $25 per linear foot, or $500 to $3,800 for 50 to 150 feet, plus $500 to $1,700 for a subpanel.
Does a detached garage need a subpanel?
If it has more than one circuit, yes. HomeGuide says structures needing more than one circuit need a subpanel, at $500 to $1,700.
How much does it cost to install an EV charger in a garage?
HomeAdvisor puts installation at $554 to $1,380, $967 on average. If the garage needs a new 240-volt circuit or panel upgrade, add $500 to $2,000 or more.
Do garage outlets need to be GFCI?
Yes. HomeGuide notes the National Electrical Code requires GFCI protection in garages and at least one outlet per car space.
Sources
- HomeGuide, "How Much Does It Cost to Build a Garage?", January 15, 2026 Verified
- HomeGuide, "Cost to Run Electricity to a Shed, Garage, or Shop", April 5, 2023 Verified
- HomeAdvisor, "How Much Does a Detached Garage Cost?", updated June 17, 2026 Verified
- HomeAdvisor, "Electric Car Charging Installation Cost", updated June 20, 2026 Verified
- US Department of Energy, Alternative Fuels Data Center, "Charging Electric Vehicles at Home" Verified
- HomeGuide, "How Much Does a Mini Split Installation Cost?", October 8, 2025 Verified
Figures last checked October 25, 2026. National averages are a planning guide, not a quote. See our editorial policy and data sources.
