Cost to Charge by Battery Size

Most cost-to-charge questions are really lookup questions. You know roughly what your car’s battery is, you can find your rate on a bill, and what you actually want is the number where those two meet. So here are both tables, and then the small print that makes them accurate.

Step one: find your usable pack size

Battery capacity is quoted in kilowatt-hours— a measure of energy, the same unit your utility bills you in. That is the whole reason this calculation is so simple: the car’s tank and the electricity meter speak the same language, which is not true of gallons and miles per gallon.

Two figures often appear on a spec sheet: gross (or nameplate) and usable capacity. Manufacturers reserve a buffer at each end of the pack to protect the cells from being run truly flat or truly full, so usable is the smaller and the honest number for this sum. If only one is published, use it and read your answer as a slight overestimate.

The ladder below spans the current market, from small commuter packs to the largest trucks and SUVs. Find the row closest to yours.

Cost of a full charge

Read one row across and the honest headline of home charging appears: even a large 100 kWh pack costs about $18 to fill at the national average, and about $12in a cheap-power state. Read one column down and you see the other half — a big battery is not expensive per mile, it is expensive per fill, because it holds more.

The far-right column is not a hypothetical. It is Hawaii, whose 52 cents per kWh in EIA’s May 2026 table is the highest residential rate in the country and roughly 2.8 times the national average. Every other state falls somewhere between the second and seventh columns — see cost by state.

Cost per mile, where battery size disappears

Per-mile cost is the figure worth internalizing, because it is the one you compare with a gas car. And it is governed by two things only: price per kWh ÷ miles per kWh.

Battery size is nowhere in that table, and that is the point. What moves your per-mile cost is efficiency — a 4.5 mi/kWh compact and a 2.5 mi/kWh electric truck differ by nearly a factor of two at the same rate, which is a bigger swing than most people will ever get from changing utility plans. DOE and EPA publish each model’s efficiency as kWh per 100 miles on the vehicle’s label; divide 100 by that figure to get miles per kWh.

The three corrections that make it real

Charging losses, about 10%.Not all the energy leaving your meter reaches the battery — some becomes heat in the charger, the cable, the car’s onboard charger and the cells. For Level 2 charging, adding a tenth is a good working allowance. It is also one reason an ENERGY STAR listing is worth having: certified chargers draw substantially less in standby, which is the state a wall charger spends most of its life in.

You rarely charge from empty.Home charging is a top-up. If your day used 25% of the pack, you are buying 25% of the full-charge figure — on a 75 kWh car at the national average, about $3.50. That is the number that should sit in your head, not the full-charge one.

Winter is not a rounding error.DOE and EPA data put EV range loss at around 41% in mixed driving at 20°F with the cabin heater running. Those are miles you paid for and did not get, and across a northern winter it is a real line on the bill. We do that arithmetic in what winter does to your charging bill.

Does the charger change any of this?

Not the total. A 48-amp charger and a 16-amp charger delivering the same kilowatt-hours cost the same — speed moves energy faster, it does not make it cheaper. What a charger can change is when the energy moves, and on a time-of-use plan that is worth real money: shifting a whole session into an off-peak window can cut the effective rate substantially, as we set out in time-of-use charging.

So the earned recommendation from this page is narrow, and it is about scheduling and standby draw rather than amps. If your rate varies by time of day, buy something that can be told when to run — either a charger with a scheduler or a car that has one. If it does not vary, the cheapest reliable box on the wall costs you nothing extra to own.

Quick picks

Ranked on published specs, charging speed, electrical fit and value. Select a row to jump to the full write-up. We have not bench-tested these chargers — here is exactly what we do instead.

#	Product	Best for	Price
1	Emporia Level 2 EV Charger The value pick that doesn't feel cheap: a full 48 amps, ENERGY STAR listing, WiFi with genuine energy monitoring, and a 25 ft cable — for well under what the big names charge. It's the one we point most people to first.	Scheduling plus per-session energy data	$449.00 · View on Amazon Price as of September 2, 2026. #ad How we’re funded
2	EVIQO 48A Level 2 Charger A lot of charger for the money: a full 48 amps, WiFi with scheduling, ENERGY STAR, and the longest usable reach in this group thanks to a 25 ft cable plus a 40-inch input lead. A strong value alternative to Emporia if you want maximum reach.	ENERGY STAR value pick for low standby draw	$428.98 · View on Amazon $479.0010% off Price as of September 2, 2026. #ad How we’re funded
3	Grizzl-E Classic A deliberately dumb charger, and that's the point. No app, no cloud account, no firmware to fail — just a die-cast aluminum box built for a Canadian winter and rated to keep working outdoors. If you want set-and-forget, this is it.	Flat-rate homes, where scheduling adds nothing	Check price on Amazon → #ad How we’re funded

If you would rather not read off a table at all, the calculator on our cost-to-charge page takes your own rate, pack and efficiency and returns the same answer. And if you are still deciding whether the hardware is worth buying in the first place, is a Level 2 charger worth it runs the payback against the free cable that came with the car.