The Short Answer
At a typical US residential rate of $0.16/kWh, a full charge of a 75 kWh battery costs about $13, and 100 miles cost roughly $4.50 — far less than the ~$11.30 a comparable 30 mpg gas car burns on the same distance. Most home-charging EV owners end up around $35–60 per month in "fuel". Your real number depends on three factors — more on those below.
Want to run your own numbers right away? Use our free charging cost calculator.
The Formula
Cost per charge = battery capacity (kWh) × electricity rate ($/kWh) ÷ charging efficiency (~0.9)
Charging isn't lossless: a Level 2 wallbox delivers roughly 88–92% of the electricity it draws into the battery, so divide by ~0.9 to get the cost at your meter. For cost per 100 miles, it's easier to use real consumption including charging losses — around 26–30 kWh/100 miles for most EVs.
Example Costs by Electricity Rate (28 kWh/100 mi)
| Power source | Price/kWh | Cost per 100 miles | Full charge (75 kWh) |
|---|---|---|---|
| Off-peak / EV rate plan | ~$0.10 | $2.80 | ~$8 |
| US average residential | ~$0.16 | $4.50 | ~$13 |
| High-cost states / peak | ~$0.25 | $7.00 | ~$21 |
| Public Level 2 | ~$0.35 | $9.80 | ~$29 |
| DC fast charging | ~$0.50 | $14.00 | ~$42 |
For comparison: a 30 mpg gas car at $3.40/gal runs $11.30 per 100 miles. Note the uncomfortable truth in the last row: if you charge mostly at DC fast chargers, you can pay more than gas. Your charging mix decides everything.
The Three Factors That Actually Matter
1. Your Rate — and When You Charge
Time-of-use plans can cut off-peak rates 40–70% below peak, and many utilities offer dedicated EV plans. Scheduling your wallbox for the overnight window is the single biggest lever on your bill — worth $200–400 a year at typical mileage, with zero loss of comfort.
2. Your Charging Mix
Home is almost always cheapest. A month with two road trips and lots of fast charging looks completely different from a home-only month. That's why generic calculator averages mislead — your mix is individual.
3. Your Car's Real Efficiency
EPA ratings assume ideal conditions. Winter, highway speeds, and preconditioning push real consumption up 20–40%. Your true cost per mile only shows up in your actual charging data.
Stop Estimating — Measure It
Your wallbox already knows your numbers; ChargeDoc reads them:
- Connect your wallbox (go-e Charger, Wallbox Pulsar, Tesla Wall Connector and more) — every session is captured automatically with kWh.
- Set your electricity rate — flat or time-of-use. ChargeDoc prices every session at what you actually pay.
- Read your dashboard: monthly cost, total kWh, and your average price per kWh — the one number that tells you whether your charging strategy works.
- Watch the trend: switched to an off-peak schedule? You'll see the average drop the following month.
And if you're wondering how that stacks up against gasoline: EV vs. Gas — how much are you really saving?
Bottom Line
Home charging at an average rate costs about $4–5 per 100 miles — and with an off-peak plan, well under $3 — making it clearly cheaper than gas in almost every scenario. What matters isn't the internet's average; it's your rate, your charging mix, and your real consumption. Run your scenario in the charging cost calculator — or let ChargeDoc record your real costs automatically.