Home EV Charging Cost Calculator

Wondering what your electric car really costs to run each month? This EV charging cost calculator turns three numbers you already know, how far you drive, your car's efficiency in miles per kWh, and your electricity rate, into a clear monthly charging bill. It splits your bill between home charging and public charging, because that mix is where most estimates go wrong: home electricity typically runs $0.13, $0.17 per kWh in the US (around 26p in the UK), while public DC fast chargers can bill two to three times more per kilowatt hour. Add your gas price and the fuel economy of the car you are comparing against, and the tool shows your cost per mile and how much you save, or don't, versus petrol. Behind the math: monthly energy equals miles divided by efficiency; each kWh is billed at the rate of the socket it came from; and charging losses of 5 to 15% in the onboard charger mean the grid delivers slightly more than the battery keeps. Plug in your own tariff, including any EV time of use plan, and get a number you can actually budget with.

Last updated: October 22, 2026

Written by Ateeq Fareedi · Last updated October 22, 2026

The formula

Monthly energy (kWh) = miles driven ÷ EV efficiency (mi/kWh)
Home cost = monthly kWh × home share × home rate; public cost = monthly kWh × public share × public rate
Total monthly charging cost = home cost + public cost
Cost per mile = total monthly charging cost ÷ miles driven
Savings vs gas = (miles ÷ gas-car mpg × gas price) − total monthly charging cost

A worked example

Drive 1,000 miles a month in an EV that manages 3.5 miles per kWh: that is 285.7 kWh of energy. Charge 80% at home ($0.16/kWh = $36.57) and 20% at public chargers ($0.35/kWh = $20.00) and your monthly bill is $56.57, about 5.7 cents a mile. A petrol car doing 28 mpg at $3.20 a gallon costs $114.29 for the same miles, so the EV saves $57.71 a month.

More about the EV Charging Cost Calculator

How EV charging cost actually works

The kilowatt hour is the gallon of electricity: your utility bills you a fixed number of cents per kWh, and your EV stores energy in a battery measured the same way. Charging cost is simply energy multiplied by the rate, a 60 kWh battery filled at $0.16/kWh costs $9.60 in pure energy terms.

One wrinkle the headline math hides: charging losses. Your car's onboard charger converts AC wall power to DC battery power and sheds 5 to 15% as heat, so the metered energy, the part you pay for, is always a little higher than what the battery reports receiving. Home Level 2 chargers (EVSE wallboxes) are typically 88 to 95% efficient.

Home vs public charging: the price gap

Where you charge matters more than what you drive. US residential electricity averages $0.13, $0.17 per kWh (about 26p/kWh in the UK in 2026), while public DC fast chargers typically bill $0.30, $0.55 per kWh, two to three times the home price. AC destination chargers at malls and offices sit between the two.

That spread is why this calculator splits the bill by charging mix. A driver who charges 100% at home pays roughly half what a driver relying on DC fast chargers pays for the same miles. Treat public charging as a top up convenience, not your main fuel source, and the monthly numbers stay small.

Find your EV's real efficiency

Efficiency in miles per kWh is the number that turns your driving into kilowatt hours, and it is printed on your dashboard or trip computer, look for mi/kWh, or divide 1,000 by a Wh/mi figure to convert. Most mainstream EVs land between 3 and 4 miles per kWh in mixed driving.

Use the EPA combined rating for your model as a starting point, then adjust for reality: cold winter months can cut efficiency 10 to 20% because cabin heating draws real power, while gentle city driving beats highway speeds. If in doubt, start at 3.5 and refine after a month of actual driving.

EV vs petrol: the per mile comparison

Cost per mile is the apples to apples number that ends the EV versus petrol argument. At 3.5 mi/kWh and $0.16/kWh, an EV costs about 4.6 cents a mile; a petrol car doing 28 mpg at $3.20 a gallon costs about 11.4 cents a mile, roughly 2.5× more. The calculator works both sides out automatically from your inputs.

For the full ownership picture, pair this with our Monthly Fuel Cost Calculator to budget the petrol side precisely, the monthly saving it shows here is the number that justifies a home wallbox or a cheaper EV electricity tariff.

Five ways to cut your charging bill

First, check whether your utility offers an EV or time of use tariff, overnight rates can be dramatically cheaper than the standard daytime price. Second, shift as much charging home as possible, since public fast charging is the most expensive energy you will ever buy for the car.

Third, keep public fast charging sessions to the 10 to 80% battery window, where charging is fastest and cheapest per kWh. Fourth, precondition the cabin while still plugged in so the battery's energy goes to miles, not heat. And fifth, explore the rest of our car & auto calculators (/car-auto-calculators/) for fuel budgets, car loans and lease vs buy math, including the Car Loan vs Lease Calculator if you are still deciding how to buy the EV itself.

Worked example: pricing 40 kWh two different ways

Say your car needs 40 kWh to refill after a long trip. At a hypothetical home rate of $0.17 per kWh, that energy costs 40 × 0.17 = $6.80. At a public rapid charger charging $0.48 per kWh, the identical 40 kWh costs $19.20, nearly three times as much for the same electrons in the same battery. The car does not care where the energy came from; your wallet does.

Now add charging losses. Delivering 40 kWh into the battery typically means drawing roughly 44.4 kWh from the wall, because about a tenth of the energy is lost as heat in the cable and the car’s charging hardware. At the home rate that drawn energy costs about $7.56 rather than $6.80. Tick the losses option in the calculator and your estimate quietly absorbs this instead of flattering you.

Cost per mile: the figure that settles the argument

Total charge costs are hard to compare with a tank of fuel, so convert to cost per mile. If your car uses 30 kWh per 100 miles, that is 0.30 kWh per mile; at $0.17 per kWh home energy, driving costs 0.30 × 0.17 = about 5 cents a mile in electricity. Run the same car on public rapid charging at $0.48 and the figure jumps to roughly 14 cents a mile.

The comparison cuts both ways, which is why it is useful. A home charged EV at 5 cents a mile undercuts almost any petrol car on fuel alone, while a driver who relies entirely on rapid chargers may save far less than the headlines promised. Your personal answer depends on your home versus public mix, and the calculator lets you weight the two rates instead of pretending one rate describes your life.

Where home charging estimates usually go wrong

The first wrong turn is pricing the battery instead of the energy. A 60 kWh battery rarely takes 60 kWh from empty in real life, because drivers plug in at 30 percent and leave at 80, the energy actually bought is the difference, plus losses. Estimate from the kilowatt hours you add between those two percentages, not from the badge on the battery.

The second is using the wrong electricity price. Many households pay different rates at different hours, and a flat average from a bill that includes fixed daily charges overstates the per kWh cost of charging. Use the marginal rate, the price of one more kilowatt hour at the time you actually charge, and the overnight figure you were promised is the one your estimate will match.

How to use the EV Charging Cost Calculator

Enter your monthly mileage and your EV's efficiency in miles per kWh.
Add your home electricity rate and the public charging rate you usually pay.
Set the share of charging you do at home, push it toward 100% for the cheapest bill.
Enter a gas price and the mpg of the petrol car you are comparing with, then hit Calculate.

Frequently asked questions

Is home charging really cheaper than public charging?

Yes, by a wide margin. Home electricity in the US averages $0.13, $0.17 per kWh, while public DC fast chargers typically charge $0.30, $0.55 per kWh, two to three times more. Charging at home overnight covers most daily driving for the least money; public charging is best treated as a top up convenience, not the main fuel source.

How much does it cost to charge a Tesla at home?

Take the battery size, about 60 kWh for a Model 3, around 75 kWh for a Model Y, and multiply by your tariff. At $0.16/kWh a full Model 3 charge costs roughly $9.60, a Model Y about $12. You rarely charge from empty, though: topping up 50% overnight costs around $5, $6, enough for several days of typical commuting.

Should I account for charging losses?

Yes, if you want the bill to match reality. Home Level 2 chargers are typically 88 to 95% efficient, meaning 5 to 12% of the energy you pay for never reaches the battery. It is lost as heat in the onboard charger. For planning purposes, add about 10% to the energy your car reports using; this calculator's mileage based estimate already implies real world efficiency.

What is the difference between kW and kWh when charging an EV?

Kilowatts (kW) describe how fast energy flows, the charging speed, while kilowatt hours (kWh) describe how much energy the battery actually received. Your electricity bill, and this calculator, are based on kWh.

Is it cheaper to charge an EV overnight?

If your electricity tariff has off peak or time of use pricing, charging during the cheaper overnight window lowers your cost per kWh. On a flat rate tariff the time of day makes no difference to the price.

How much does it cost to charge an EV at home?

Multiply the kWh needed by your electricity rate. A 60-kWh battery at $0.16/kWh costs $9.60 for a full charge, good for roughly 200 to 250 miles, or about 4 to 5 cents per mile. Public fast chargers cost 2 to 3× more, typically $0.30, $0.50/kWh.

Is charging an EV actually cheaper than petrol?

Usually yes, home charging typically costs the equivalent of paying a fraction of petrol prices per kilometer, often 50 to 70% less than fueling a petrol car. Public fast chargers are pricier but still generally beat petrol; the real savings come from overnight home charging on off peak rates. Factor in lower maintenance (no oil changes, fewer brake jobs) and the total cost gap widens further.

How much does it cost to add 100 miles of range at home?

Work from your car’s efficiency. A car using 30 kWh per 100 miles needs 30 kWh for that range; at a home rate of $0.17 per kWh the energy costs $5.10, or around $5.67 once typical charging losses are included. Efficient smaller cars using 25 kWh per 100 miles pay less, heavier ones more. The calculator’s per mile output does this arithmetic with your own rate and efficiency figures.

Can I include rooftop solar in my charging cost?

Yes, treat the electricity your panels send to the car as having a cost equal to what you would otherwise earn or save by using it elsewhere. If surplus solar would be exported for a small feed in payment, charging with it costs roughly that forgone payment per kilowatt hour, which is often very cheap indeed. If the panels simply offset energy you would have bought, use your normal import rate. Enter that figure as your home rate.

How do I find the per kWh rate on my electricity bill?

Look for the usage charge lines rather than the bill total. Electricity bills usually separate a fixed daily supply charge from per kilowatt hour usage charges, and some add supply and delivery components that both scale with usage, add those per kWh parts together for your true rate. If you are on a time of use tariff there will be several usage lines; pick the one matching the hours you charge, which for most home charging is the overnight off peak line.

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