Should you buy your own EV charger, or let the installer supply it?
Let the installer supply it unless you have a specific reason not to, and the reason is almost never price. What you are really choosing is who owns the problem when the unit fails: supply your own and the hardware claim is yours to chase while the installer's warranty covers only their wiring, so a failure eighteen months in becomes two phone calls that point at each other. The sequencing matters as much as the decision. Buy the charger after the load calculation, never before, because the amperage your service can actually support decides which models are candidates at all.
Updated 2026-08-20
The trade is warranty and responsibility, not price
It is worth more than the hundred or two hundred dollars of markup that most of the internet argues about.
Look at the last two rows
The decision people agonise over moves a few per cent of the total, and it moves the responsibility question by a lot. That is a poor trade to make on price.There is one place where shopping the hardware yourself genuinely pays: if the installer's quoted charger is markedly more expensive than the same model retail, ask them to price the job with an owner-supplied unit and compare the two totals. A reasonable installer will do that without complaint and will tell you plainly what it changes about the warranty. An installer who refuses to unbundle it has told you where their margin lives.
The sequencing point everyone gets backwards
Most people buy it first, because the charger is the fun part and the electrician is the boring part, and then discover their service supports 32 amps and they own a 48-amp unit.The chain runs one way. The load calculation tells you how much spare capacity the service has. That decides the circuit you can install. The circuit decides the maximum continuous current, because the code holds a continuous load to 80 per cent of the circuit rating. And that current decides which chargers are candidates. Working from the charger backwards means picking a number first and hoping the house agrees with it.
The mistake the last two rows describe
The common 50-amp household receptacle cannot carry it. Plenty of people buy a 48-amp unit intending to plug it in, and end up either paying for a hardwired installation they had not budgeted for or running the unit derated to 40 amps, which makes the purchase pointless.It is also worth asking whether you need the top of that table at all. Two hundred and thirty miles overnight covers essentially any domestic use. Insisting on the maximum is the most common reason a household ends up quoted for a service upgrade it does not need.
When supplying your own is the right answer
In all four cases, send the manufacturer's specification sheet to the installer before the quote is finalised, not on the morning of the install. They need the amperage, the enclosure rating, the mounting dimensions, the knockout locations and whether it is hardwired or corded. Half the problems with owner-supplied equipment are not really about who bought it; they are about the installer meeting it for the first time on the day.
How it goes wrong
Notice that only the first two are electrical. The rest are logistics, and logistics is exactly what you take on when you become the supplier.
If you do supply it, do these three things
None of this takes more than half an hour in total, and it removes most of the downside of being your own supplier.
Do installers mark up the charger?
Usually, yes, and that markup is what buys you a single point of responsibility when the unit fails. Hardware is roughly $300 to $800 of a job that runs $800 to $3,000 for a straightforward install, so it is a small share of the total. Ask for the job priced both ways if you want to see the number.
What amperage charger should I buy?
The one the load calculation supports, not the largest available. A 32-amp unit adds around 230 miles in a ten-hour night, which covers essentially any domestic use. Buying more amperage than the service can carry is the most common route to a service upgrade nobody needed.
Can I buy a used EV charger?
You can, and you generally lose the manufacturer warranty in doing so, because most warranties run to the original purchaser and many require registration and proof of professional installation. On equipment that carries full current for hours a night, that is a meaningful thing to give up for a modest saving.
Does the charger brand change the installation cost?
Barely. What changes the cost is amperage, whether it is hardwired or corded, whether it is indoors or out, and how far the run is. Two units at the same amperage and connection type are the same day's work regardless of the badge.
Do I need a 48-amp charger?
Almost certainly not at home. It requires a 60-amp circuit, it must be hardwired because no ordinary household receptacle is rated for it, and it earns its extra cost only where a car regularly arrives nearly empty and has to leave nearly full within a few hours.
Will the installer warranty a charger I supplied?
They will warranty their workmanship — the circuit, the terminations, the mounting. The hardware is between you and the manufacturer. Get that split written on the quote, including who pays the labour to remove and refit a replacement unit, because that is the line that turns into an argument.
- NFPA 70, National Electrical Code — Article 625 and the continuous-load rule behind the 80 per cent derating in the amperage table. Adoption of any edition is by jurisdiction.
- US DOE Alternative Fuels Data Center — Electric Vehicle Charging Stations, for charging levels and connector types
- Qmerit — Understanding your EV home charging station costs for installation, for the hardware and labour split
- HomeAdvisor — Cost to install an electric vehicle charging station, for the residential installed range
- IRS — Alternative Fuel Vehicle Refueling Property Credit, for the Section 30C termination date
Find out what amperage your job supports first
The charger decision is downstream of the circuit, and the circuit is downstream of the panel. Tell us what is in the panel and where the car parks, and you get an installed-price range for the circuit that is actually available to you.