SnapEnergyLab

EV tools

Cost to charge an EV at home

A full charge, a cost per mile, and a monthly total from your own mileage — all based on the energy your meter actually records.

How much does it cost to fully charge an electric car at home?

Filling a 75 kWh pack from empty puts 75 kWh into the battery but draws 83.3 kWh from the wall once 10% charging losses are included. At $0.180/kWh that is $15.00 for the full charge, or $0.057 per mile at 3.5 mi/kWh. Driving 1,000 miles a month works out at $57.14 per month and $685.71 per year.

The same charge at different electricity rates

75 kWh pack, 0→100%, 10% charging loss, 3.5 mi/kWh, 1,000 miles per month.
Electricity rateFull chargePer milePer monthPer year
$0.100/kWh$8.33$0.032$31.75$380.95
$0.140/kWh$11.67$0.044$44.44$533.33
$0.180/kWh$15.00$0.057$57.14$685.71
$0.250/kWh$20.83$0.079$79.37$952.38
$0.350/kWh$29.17$0.111$111.11$1,333

Adjust for your car and tariff

Your inputs

Scenario: charger

Site default: 10%. Energy lost between the socket and the battery pack; measured AC efficiency is typically 85–93%.

$9.00

to charge from 20% to 80%

45.0 kWh into the pack, 50.0 kWh drawn from the wall

Calculated from your inputs
Energy to pack
45.0 kWh
Energy from wall
50.0 kWh
Charge cost
$9.00
Charging time
6 h 45 min

Cost per mile

$0.057

Wall energy per mile × rate, so it reflects what the meter records.

Monthly charging cost

$57.14

Based on 1,000 miles per month at 3.5 mi/kWh.

Annual charging cost

$685.71

Distance × wall energy per mile × rate, scaled to 12 average months.

Pack energy and wall energy are different numbers

Your utility bills the wall figure. The extra 10% covers the onboard charger, cable losses and battery thermal management, which is why a 75 kWh pack costs more than 75 kWh to fill.

Method

  1. 75 kWh × 60% = 45 kWh added to the pack
  2. 45 kWh ÷ 0.9 = 50 kWh drawn from the wall
  3. 50 kWh × 0.18 = 9 USD
  4. 50 kWh ÷ 7.4 kW = 6.757 hours
  5. Wall energy per mile: 1 ÷ 3.5 mi/kWh ÷ 0.9 = 0.317 kWh/mile
  6. 0.317 kWh/mile × 0.18 = 0.057 USD/mile
  7. 1000 miles ÷ 3.5 mi/kWh ÷ 0.9 = 317.46 kWh from the wall per average month
  8. 317.46 kWh × 0.18 = 57.143 USD per average month
  9. 57.143 × 12 average months = 685.714 USD per year

Assumptions

  • SnapEnergyLab default: 10% AC charging loss between the wall socket and the battery pack (editable). Measured AC charging efficiency typically falls between 85% and 93%.
  • Charging time is an idealized estimate based on constant charger power.
  • Real charging may be slower because of vehicle onboard-charger limits, thermal management, battery temperature and charging taper near high state of charge.
  • Electricity rate of 0.18 USD/kWh (editable).
  • Vehicle efficiency of 3.5 mi/kWh is measured at the battery pack, so the 10% charging loss is added on top of it to get energy drawn from the wall.

What can change the result?

  • Your tariff, especially if a dedicated overnight EV rate is available
  • Real-world efficiency, which drops noticeably in cold weather and at highway speeds
  • Charging losses, higher when the battery needs preconditioning
  • Monthly mileage, the single biggest driver of the annual figure
  • Any share of charging done on public networks at higher prices

Comparing this with a petrol or diesel car

Cost per mile is the only fair comparison, and it needs the same treatment on both sides: fuel price divided by real observed economy, not the manufacturer’s figure. At $0.180/kWh and 3.5 mi/kWh the electricity works out at $0.057 per mile, roughly 6 cents.

This is a running-cost comparison only. Purchase price, insurance, depreciation, maintenance, charger installation and any incentives all sit outside it, and for most buyers those items decide the overall economics more than the per-mile figure does.

Your next decision

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