One of the biggest financial arguments for switching to an electric vehicle is fuel cost savings. But how much does home charging actually cost — and how does it compare to what you were spending at the gas pump?
This guide walks through the exact formula, provides worked examples for common EV battery sizes, compares the numbers to gasoline, and covers strategies for reducing your monthly charging bill through smart rate selection.
The Cost Formula
Calculating the cost to charge your EV at home is straightforward:
Example: 75 kWh battery × 60% charge added = 45 kWh used
Your electricity rate is the only variable that differs by location — you'll find it on your monthly utility bill, usually expressed as cents per kilowatt-hour. Battery capacity is fixed for your vehicle. The charge percentage is simply how much you're adding in a given session.
kWh added: 75 × 0.60 = 45 kWh
Cost: 45 × $0.16 = $7.20 per session
Electricity Rates Across the United States
Electricity rates vary significantly by state and utility. Here's a representative range to help you benchmark your own situation:
| Rate Category | Approx. Rate ($/kWh) | Example States |
|---|---|---|
| Very low | $0.07–0.10 | Louisiana, Idaho, Oklahoma, Arkansas |
| Below average | $0.10–0.13 | Texas, Tennessee, Kansas, Georgia |
| US average | $0.14–0.17 | Ohio, Florida, North Carolina, Missouri |
| Above average | $0.18–0.24 | New York, Michigan, Oregon, Colorado |
| High | $0.25–0.35+ | California, Hawaii, Connecticut, Massachusetts |
Rates change periodically. Always check your current bill for your actual rate.
Cost by Battery Size: Three Common EVs
Battery size is the biggest factor in total charging cost. Here's how the numbers break down across three common battery sizes for a full 0–100% charge at three different electricity rates:
| Battery Size | At $0.10/kWh | At $0.16/kWh | At $0.28/kWh |
|---|---|---|---|
| 40 kWh (smaller EV / PHEV) | $4.00 | $6.40 | $11.20 |
| 75 kWh (mid-size EV) | $7.50 | $12.00 | $21.00 |
| 100 kWh (long-range EV) | $10.00 | $16.00 | $28.00 |
Notice how even in high-rate markets, filling a 100 kWh battery to 100% costs less than $30. A gasoline car with a 15-gallon tank would cost $52–$65 to fill at typical pump prices.
EV Charging vs. Gasoline: The Real Comparison
A fair fuel cost comparison requires converting both to cost per mile, not cost per fill-up — because EV and gasoline tanks aren't the same size.
(75 kWh · 3.5 mi/kWh · $0.16/kWh)
(30 MPG at typical pump price)
The comparison above shows home EV charging at roughly one-third the per-mile fuel cost of a gasoline vehicle. Even in high-electricity-rate states like California, the math still strongly favors EVs:
EV: $0.28/kWh ÷ 3.5 mi/kWh = $0.08/mile
Gasoline at typical prices: $0.13–0.17/mile at 28–32 MPG
EV still wins by a significant margin.
Annual Fuel Savings
At 12,000 miles per year — a common US average — the savings add up quickly:
| Scenario | Cost per Mile | Annual Fuel Cost (12k miles) |
|---|---|---|
| EV at $0.10/kWh (3.5 mi/kWh) | $0.029 | ~$343 |
| EV at $0.16/kWh (3.5 mi/kWh) | $0.046 | ~$549 |
| EV at $0.28/kWh (3.5 mi/kWh) | $0.080 | ~$960 |
| Gas vehicle at 30 MPG | $0.13–0.17 | ~$1,560–$2,040 |
Time-of-Use Rates: The Biggest Charging Savings
Many utilities offer time-of-use (TOU) electricity rate plans that charge different prices depending on when you use electricity. Demand on the grid peaks in late afternoon and early evening — so utilities incentivize customers to shift usage to off-peak hours with significantly lower rates.
A TOU plan might offer:
- Off-peak hours: $0.08–0.12/kWh (overnight, typically 9 PM–6 AM or midnight–6 AM)
- Mid-peak hours: $0.14–0.18/kWh (daytime)
- Peak hours: $0.30–0.50/kWh (late afternoon and evening)
For EV owners, this is a significant opportunity. Scheduling your car to charge overnight at off-peak rates can cut your charging cost by 40–60% compared to charging during peak hours.
Schedule overnight charging: Most EVs let you set a charging schedule in the app or infotainment system. Set charging to start after 9 PM or midnight and finish before 6 AM to consistently hit off-peak rates. Smart EVSE units also support scheduling from their companion apps.
How to Access TOU Rates
Not all utilities offer TOU plans, and enrollment isn't always automatic. To take advantage:
- Contact your utility or check their website for available rate plans
- Look specifically for EV rate plans — many utilities offer dedicated EV tariffs with lower off-peak rates for customers with electric vehicles
- Compare your estimated annual cost under each plan using your average consumption and EV charging needs
- Enroll — the switch is usually free and takes effect on your next billing cycle
Monthly Charging Cost Estimates
For a complete picture, here's what monthly home charging typically costs at different driving volumes, using a 75 kWh battery at 3.5 mi/kWh efficiency:
| Monthly Miles | kWh Used | At $0.10/kWh | At $0.16/kWh | At $0.28/kWh |
|---|---|---|---|---|
| 500 miles/month | ~143 kWh | ~$14 | ~$23 | ~$40 |
| 750 miles/month | ~214 kWh | ~$21 | ~$34 | ~$60 |
| 1,000 miles/month | ~286 kWh | ~$29 | ~$46 | ~$80 |
| 1,500 miles/month | ~429 kWh | ~$43 | ~$69 | ~$120 |
These are home-charging-only estimates. Public charging sessions add additional cost.
Cost of Installing a Level 2 Charger at Home
If you're still relying on a Level 1 outlet, upgrading to Level 2 is one of the best investments you can make as an EV owner. Not for speed alone — but because you'll always wake up to a fully charged car without thinking about it.
What Level 2 Installation Costs
| Component | Typical Cost Range |
|---|---|
| EVSE unit (basic plug-in, NEMA 14-50) | $150–300 |
| EVSE unit (smart Wi-Fi, with scheduling) | $350–700 |
| Electrician labor (NEMA 14-50 outlet install) | $200–400 |
| Hardwired EVSE installation | $300–600 |
| Panel upgrade (if needed) | $1,000–3,000 |
| Permit (varies by jurisdiction) | $50–200 |
A straightforward install — adding a NEMA 14-50 outlet to an existing panel with adequate capacity — typically runs $400–800 total. More complex installations with panel upgrades can reach $2,000–4,000, but those cases are less common in homes built or renovated in recent decades.
Federal Tax Credits
The federal Alternative Fuel Vehicle Refueling Property Credit may allow homeowners to claim up to 30% of the cost of EVSE equipment and installation, subject to annual caps and eligibility requirements. Check the IRS website or consult a tax professional for the current rules in your situation.
Break-even calculation: If installing Level 2 costs $600 and you currently spend $1,200 more per year on gasoline than you would on home charging, the charger pays for itself in under six months in fuel savings alone — before accounting for any tax credits.
Calculate Your Exact Charging Cost
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