What does home EV charging cost?

People type this into search every day: home EV charging cost calculator.

The usual answer is “electricity is cheaper than gas.” That can be true. You still need the kilometres, the kWh the car uses, the loss in the cable, and the rate on the last statement.

The home EV charging calculator prices a month at one rate. All charging happens at the price you type. Fixed charger and demand fees stay out. Those are the tool’s assumptions.

This page is a labeled example. It is not your utility tariff, and it is not a fuel-economy sticker.

Distance, efficiency, loss, then the rate

The calculator uses:

distance ÷ 100 × kWh per 100 km × (1 + charging loss) × price per kWh

1,200 km at 18 kWh / 100 km is 216 kWh at the wheels. A 10% loss makes that 237.6 kWh at the meter.

DOE’s estimating appliance energy use page is watts times hours, then kWh times the rate. An EV is the same kWh times the rate. The hours hide inside the efficiency number.

Look up a model on fueleconomy.gov. Type that model’s kWh / 100 km, not a national average I would have to invent.

The EIA Electricity Monthly Update puts US residential average revenue at 18.31 cents / kWh in July 2026. August 2026 on EIA Table 5.3 is 18.16 cents / kWh. Neither number is your overnight EV rate. The calculator default is $0.28.

Example 1: the published $66.53 month

Here are the calculator defaults:

• distance driven per month: 1,200 km
• vehicle efficiency: 18 kWh / 100 km
• electricity price: $0.28 / kWh
• charging loss: 10%

Wheel energy: 1,200 ÷ 100 × 18 = 216 kWh

Grid energy: 216 × 1.10 = 237.6 kWh

Month: 237.6 × 0.28 = $66.53

Cost / 100 mi: $8.92

Annual charging: $798.34

The US profile prints distance in miles. 1,200 km is 1,200 × 0.621371192 = 745.6 mi. 18 kWh / 100 km displays as 29.0 kWh / 100 mi.

21.6 kWh of loss at $0.28 is $6.05 a month, $72.58 a year. The loss line is small next to the 216 kWh. It is not zero.

Example 2: the July 2026 EIA rate

Keep 1,200 km, 18 kWh / 100 km, and 10% loss. Set the rate to $0.1831.

Month: 237.6 × 0.1831 = $43.50

Cost / 100 mi: $5.83

Annual: $522.05

The default $0.28 month was $66.53. The EIA-average path is $23.03 cheaper on the same 237.6 kWh. That is a national residential average, not an EV overnight tariff.

August 2026 at $0.1816: month $43.15. Annual $517.78.

The time-of-use default is $0.34 peak and $0.14 off-peak. EIA does not publish peak and off-peak retail rates. Their FAQ says so. Type the two lines from your tariff.

Example 3: what if I change only the distance

Hold 18 kWh / 100 km, $0.28, and 10%.

• 800 km: grid 158.4 kWh. Month $44.35. Year $532.22.
• 1,200 km (default): grid 237.6 kWh. Month $66.53. Year $798.34.
• 1,600 km: grid 316.8 kWh. Month $88.70. Year $1,064.45.
• 2,000 km: grid 396 kWh. Month $110.88. Year $1,330.56.

Cost per 100 miles stays $8.92. The month scales with the kilometres.

Example 4: a more efficient car, and a thirstier one

Hold 1,200 km, $0.28, and 10%.

15 kWh / 100 km: grid 198 kWh. Month $55.44. Year $665.28. Cost / 100 mi $7.44.

18 kWh / 100 km (default): $66.53.

22 kWh / 100 km: grid 290.4 kWh. Month $81.31. Year $975.74. Cost / 100 mi $10.90.

The 15-to-22 spread is $25.87 a month, $310.46 a year, on the same 1,200 km. That gap is the efficiency box, not the utility.

Example 5: drop the 10% loss, or raise it

Hold 1,200 km, 18 kWh / 100 km, and $0.28.

0% loss: grid 216 kWh. Month $60.48. Year $725.76. Cost / 100 mi $8.11.

10% loss (default): $66.53.

15% loss: grid 248.4 kWh. Month $69.55. Year $834.62. Cost / 100 mi $9.33.

Skipping the loss understates the default month by $6.05. That is the common mistake: people multiply 216 × 0.28 = $60.48 and call it the bill. The meter saw 237.6 kWh.

Example 6: put 237.6 kWh on the house bill

The electricity bill estimate default is 650 kWh at $0.22, $18 fixed, 5% tax: $169.05.

Add the default EV: 650 + 237.6 = 887.6 kWh.

Usage charge: 887.6 × 0.22 = $195.27

Tax: (195.27 + 18) × 0.05 = $10.66

Bill: $223.94

The EV added 223.94 − 169.05 = $54.89 on that $0.22 tariff, not the $66.53 you get at $0.28. Different rates, same 237.6 kWh.

The time-of-use default month is $153.00 (220 kWh at $0.34, 430 kWh at $0.14, $18 fixed). Charge the 237.6 kWh off-peak:

Off-peak use: 430 + 237.6 = 667.6 kWh

Month: $186.26

The extra is 186.26 − 153.00 = $33.26, which is 237.6 × 0.14. Charge that same 237.6 kWh on-peak and the extra is 237.6 × 0.34 = $80.78. The window matters more than the 10% loss.

The appliance electricity post is watts and hours on one device. An EV is a large device with a kilometres box.

Example 7: a short 600 km month at the EIA rate

600 km, 16 kWh / 100 km, $0.1831, 10% loss.

Wheel energy: 6 × 16 = 96 kWh

Grid: 96 × 1.10 = 105.6 kWh

Month: $19.34

Year: $232.02

Cost / 100 mi: $5.19

That is a light local month. It is not a highway year.

Example 8: a highway month, and a road-trip neighbor

Highway, labeled: 1,800 km, 21 kWh / 100 km, $0.28, 12% loss.

Wheel energy: 18 × 21 = 378 kWh

Grid: 378 × 1.12 = 423.4 kWh (prints 423.4 kWh)

Month: $118.54

Year: $1,422.49

Cost / 100 mi: $10.60

The EV road-trip charging default is 850 km, 18 kWh / 100 km, 70% fast charging at $0.58, 30% at $0.25, 10% loss: $80.95 for the trip, 168.3 kWh, blended $0.48 / kWh.

Home at the $0.28 default for that same 850 km, 18 kWh / 100 km, 10% loss:

Grid: 8.5 × 18 × 1.10 = 168.3 kWh

Cost: 168.3 × 0.28 = $47.12

The road-trip card is $33.83 above that home price because most of the energy is at $0.58. The road-trip fuel post is the gasoline neighbor. Its default 850 km is $111.96.

Eight charging months side by side

Open the home EV charging calculator with last month’s kilometres and the supply-plus-delivery rate on the statement. If you charge at night, type the off-peak line. If you skip the loss box, the $66.53 month becomes the $60.48 mistake.