You bought the car, and the dealer said "you'll just need an outlet in the garage." Then the first electrician who visited looked at your panel, made a face, and started talking about service upgrades and load calculations. Neither of those conversations told you what the job actually is.
Here is the takeaway up front: the charger is the cheap part. A Level 2 unit is a commodity box. What decides whether this job costs a few hundred dollars or several thousand is the state of your electrical service — how much spare capacity the panel has, how far the charger sits from it, and whether your jurisdiction wants a permit and an inspection. Get a load calculation done before you accept any price, because a quote written without one is a guess.
Level 1 vs Level 2: what you actually need
Level 1 is the cord that came with the car, plugged into an ordinary 120V outlet. It draws roughly 1.3–1.9 kW and adds around 3–5 miles of range per hour. That sounds useless until you do the arithmetic: over twelve hours, that is 40–60 miles added while you sleep. If your daily driving is a short commute, Level 1 may genuinely be enough, and it costs nothing to install.
Level 2 runs on a 240V circuit — the same class of supply as an electric range or dryer. Depending on the circuit, it delivers roughly 7 kW to 11.5 kW and adds on the order of 20–30 miles of range per hour. This is what most people mean by "installing a charger," and it is the right answer if you drive a lot, have a large battery, or share a car between drivers.
The practical rule: size the circuit to your driving, not to the charger's maximum. A 32-amp charger on a 40-amp circuit covers most household needs and is far easier to fit into an existing panel than a 48-amp unit demanding 60 amps. Buying the biggest charger available is the most common way people talk themselves into a panel upgrade they did not need.
Does your panel have room? The load calculation
This is the question the whole project turns on, and counting empty breaker slots does not answer it. An empty slot means physical space; it says nothing about whether the service can carry more load.
Under the National Electrical Code, EV charging is treated as a continuous load, which means the circuit must be rated at 125% of the charger's draw. A 48-amp charger therefore needs a 60-amp breaker and conductors sized to match; a 32-amp charger needs 40 amps. That multiplier is why chargers eat capacity faster than people expect.
An electrician has a few legitimate routes to prove the capacity exists:
- A standard load calculation (NEC Article 220) totalling the dwelling's connected loads against the service rating. Conservative, and often the reason a 100-amp service fails.
- A metered-demand calculation (NEC 220.87), which uses the actual maximum demand recorded over the past year — usually available from the utility — instead of assumed loads. Real houses use far less than the assumption tables suggest, so this frequently passes a panel the standard calculation fails. Ask whether the electrician has considered it.
- Load management (EVEMS). An energy management system throttles or interrupts charging when the rest of the house is drawing heavily, so the charger is not counted at full value. Many modern chargers have this built in; separate meter- or panel-mounted devices do the same job. It is often far cheaper than upgrading the service and is explicitly permitted by the code — but it must be installed and documented properly, not just enabled in an app.
If none of those work, you are looking at a service upgrade — a new panel, possibly a new meter base, service conductors, and utility coordination. It is a real project with its own permit, and where a modest charger job becomes a five-figure conversation. Get a second opinion first, asking specifically about load management as an alternative.
Hardwired or plug-in?
Both are code-compliant; they trade off differently.
Plug-in (typically a NEMA 14-50 receptacle) lets you unplug the unit, take it when you move, and swap a failed charger without an electrician. The catch: a 240V garage receptacle requires GFCI protection, and some chargers have internal ground-fault protection that nuisance-trips against an upstream GFCI breaker. The receptacle is also a wear item — cheap ones have a poor reputation for heat damage under sustained 40-amp loads, so this is not the place to save twenty dollars.
Hardwired suits high-amperage units (48A chargers are generally hardwired by necessity), outdoor installations, and anywhere you want the fewest connections that can loosen and heat up.
For most 32-amp installs, either works. Above 40 amps, hardwire it.
Permits, inspection, and why you want them
Almost every US jurisdiction treats a new 240V branch circuit as permitted electrical work, and a service upgrade certainly is. Some states require municipalities to run an expedited, largely over-the-counter process for residential EV charging specifically — California's streamlined EV permitting rules are the best-known example.
Skipping the permit is a bad trade. An unpermitted circuit is a problem at resale, a potential problem with your insurer after any fire, and it removes the only independent check on whether the conductors were sized correctly for the load and the run length. Our walkthrough of the permit application process covers what the submission usually needs.
Separately, check whether your utility wants to be told. Some require notification for a load addition of this size, and many offer EV-specific time-of-use rates that change the economics far more than the install cost does. Rebates and tax credits for charging equipment change frequently — confirm what currently applies in your area rather than assuming last year's program is still open.
What drives the price
Ask three electricians and you will get three numbers, mostly because they are pricing three different amounts of work. The variables that matter:
- Distance from the panel to the charger — usually the biggest single driver. A charger on the garage wall behind the panel is a short run in conduit. One at the far end of a detached garage means trenching, a longer run, and heavier conductors to control voltage drop.
- The route. Surface conduit along a garage wall is cheap. Fishing cable through a finished basement ceiling, or cutting and patching drywall, is not.
- Conductor size. A 60-amp circuit needs meaningfully heavier copper than a 40-amp one, and long runs get upsized again for voltage drop.
- Panel work. A spare double-pole slot is easy. A panel needing a subpanel, a load-management device, or a service upgrade is a different project entirely.
- Permit and inspection fees, which vary by jurisdiction.
As a rough shape: a simple install with capacity available and a short run commonly lands in the low hundreds to around $1,500 in labor and materials. Long runs, trenching, or a subpanel push it higher, and a full service upgrade is commonly quoted in the low thousands and up. Treat those as orientation — local labor rates move them a lot.
Getting quotes you can actually compare
The failure mode is identical to any other trade: three bids that look comparable and are not. Insist each quote states, in writing:
- The charger amperage and circuit size (32A on a 40A circuit is not the same product as 48A/60A).
- Whether a load calculation was performed, by which method, and its result.
- The conductor size and run length, and whether the route is surface conduit or concealed.
- Hardwired or receptacle, and if a receptacle, which grade.
- Whether permit and inspection fees are included or excluded.
- What happens if the panel needs work — a stated hourly rate and an allowance, not silence.
That last one matters. A bid that quietly excludes panel work wins on price and then change-orders its way past the honest one. Our guide to comparing contractor quotes line by line applies directly here.
Finally, verify the electrician: an active license in your state, liability insurance, and workers' compensation if they have a crew. Work sealed inside a wall is the classic case where you cannot inspect the result yourself, so the credential is doing real work. Our contractor vetting guide covers the checks in full.
FAQ
Can I install a Level 2 charger myself? In most jurisdictions a homeowner may pull a permit for work on their own residence, but a 240V circuit is not a beginner project — conductor sizing, grounding, and continuous-load rules all have to be right, and the failure mode is a fire inside a wall. Unless you genuinely know the code, this is licensed-electrician work.
Will a 100-amp service support an EV charger? Often, yes — particularly with a 32-amp charger, gas cooking and water heating, or a load-management device. The standard load calculation frequently says no while a metered-demand calculation says yes. Have both considered before anyone quotes a service upgrade.
Do I need a permit for a plug-in charger? The charger is an appliance, but installing the 240V receptacle it plugs into is electrical work and normally requires a permit. Using an existing dryer or range outlet is a different situation, though sharing a circuit that way has its own rules and is rarely a good permanent answer.
How long does the installation take? A straightforward install with capacity available is commonly a half-day to a day, plus the inspection visit. A panel or service upgrade adds utility coordination and typically stretches across weeks, most of it waiting rather than working.
Before you shop for a charger, get a licensed electrician to do a load calculation on your actual panel — that number decides the shape and the price of this entire project. Compare quotes from licensed electricians at constico.com, and make each one show its load calculation before you sign anything.
