EV Charging Cost Per Mile: Home Electricity vs Gasoline, With the Math

EV Charging Cost Per Mile: Home Electricity vs Gasoline, With the Math

By EnergyBS Electrification Desk | October 2, 2026

Every EV-versus-gasoline comparison eventually comes down to one number: what a mile costs to drive. Not the sticker price, not the monthly bill in isolation, but the running cost per mile at your electricity price, your car's efficiency, and your local gasoline price. This guide gives you both formulas, explains where the inputs hide (your car's kWh per 100 miles rating, your delivered electricity rate, charging losses), and works complete examples with every rate labeled as an assumption so you can swap in your own numbers.

If you want the whole-home picture, including charger installation and monthly bills, start with our EV home charging guide and the step-by-step bill math in how much it costs to charge an EV at home. This page goes one level deeper, into the per-mile arithmetic itself.

The Two Formulas That Settle the Argument

EV cost per mile: take the car's consumption in kWh per 100 miles, divide by 100 to get kWh per mile, and multiply by your electricity price in dollars per kWh. The U.S. Department of Energy publishes the same formula in per-mile form: dollars per kWh multiplied by the car's kWh per mile. Your car's kWh per 100 miles figure is on its window sticker and EPA rating, and most EVs fall somewhere in the mid-20s to mid-30s depending on size, tires, and driving.

Gasoline cost per mile: take the price per gallon and divide by the car's fuel economy in miles per gallon. Barrels and refineries disappear; what remains is the number your old car was quietly charging you every mile.

Worked illustration with labeled rates. Assume a home rate of $0.16 per kWh (assumption A), gasoline at $3.60 per gallon (assumption G), an EV consuming 28 kWh per 100 miles (assumption E, a typical mid-size figure), and a gasoline car at 30 MPG (assumption M):

• EV: 28 kWh per 100 miles is 0.28 kWh per mile. 0.28 x $0.16 = $0.0448, about 4.5 cents per mile.
• Gasoline: $3.60 / 30 MPG = $0.12, about 12 cents per mile.

Over 1,000 miles, those assumptions produce $45 of home electricity versus $120 of gasoline. Over a 12,000-mile year, $540 versus $1,440. None of these outputs is a market quote; they are what the formulas return when fed assumptions A, G, E, and M. Change any input and the gap scales in direct proportion, which is exactly why the formula matters more than any single headline number. The U.S. Department of Energy's eGallon tool was built on the same idea, comparing the cost of driving an EV the same distance a gasoline car covers on one gallon; the formula above is that comparison, priced with your own inputs.

Step 1: Find Your Car's Real Consumption

The kWh per 100 miles figure printed for your car is measured at the battery and wheels under test conditions. Three adjustments turn it into a planning number:

1. Charging losses. Not every kilowatt-hour you buy reaches the battery. The charger, cable, and battery management convert some of it to heat. Level 2 home charging is fairly efficient; Level 1 charging over a household outlet wastes proportionally more, and cold weather worsens both. For planning, add a losses allowance on top of the rated consumption. This guide uses 10 percent as a labeled planning assumption in the examples below; treat your own figure as adjustable, and note that our Level 1 vs Level 2 charging comparison covers the equipment side of that choice.
2. Season and speed. Aerodynamic drag rises steeply with highway speed, and winter heating draws from the same battery. A car rated at 28 kWh per 100 miles can use meaningfully more on a cold highway trip and less in mild city driving. Budget your worst regular season, not your best.
3. Your odometer is the referee. Most EVs report consumption in the trip computer. One month of your own kWh per 100 miles readings, divided between seasons, beats any generic table.

Apply the losses allowance before the rate: an EV rated at 28 kWh per 100 miles with a 10 percent losses allowance draws about 30.8 kWh per 100 miles from the wall. At $0.16 per kWh that is about 4.9 cents per mile, not 4.5. That correction is small but real, and it is the one most cost comparisons quietly skip.

Step 2: Get Your Delivered Electricity Rate

The rate in the formula is the price you actually pay per kWh, not the generation price your utility advertises. The reliable method, which we walk through in detail in the home charging cost guide, is to take a recent bill, divide the usage-based total by the kilowatt-hours used, and use the result. That folds in delivery charges and riders that a headline rate hides.

For context when you have no bill in hand, the U.S. Energy Information Administration's Electric Power Monthly publishes average residential prices by state, which is the right source for a regional placeholder. But your delivered rate can sit well above or below a state average depending on your utility and plan, and the per-mile answer scales one-for-one with it. An EV at 30.8 wall kWh per 100 miles costs about 6.2 cents per mile at $0.20 per kWh and about 3.1 cents per mile at $0.10 per kWh. Same car, same road; only the rate changed.

Step 3: Price the Gasoline Side Honestly

The gasoline formula has the same risk as the electric one: the input has to be yours. Use the price at the stations you actually use and the MPG your car actually returns, which for most drivers is below the window-sticker figure in mixed real driving. Labeled sensitivity check using the same $3.60 assumption: at 25 MPG the cost is 14.4 cents per mile, at 35 MPG it is about 10.3 cents, and at 45 MPG for a hybrid it is 8 cents. An efficient hybrid narrows the EV gap at any electricity rate; an older truck or SUV at 18 MPG pays 20 cents per mile at the same gasoline price, and no realistic home electricity rate loses to that.

This is also where older comparison habits mislead. Quoting a single national gasoline price or a single national electricity price produces a single confident answer that matches almost nobody's driveway. The two formulas take thirty seconds each with local inputs; the discipline is in refusing to borrow someone else's.

What Time-of-Use Pricing Does to the Math

Time-of-use (TOU) plans split your electricity price by hour, and charging is the most shiftable load in the house. Where home solar generation rewards midday consumption under low export rates, TOU plans reward the opposite shift: charge after the evening peak, when the off-peak price applies. Our time-of-use electricity rates strategy guide covers plan structures and break-even thinking in depth.

Labeled illustration. Assume an off-peak price of $0.10 per kWh and an on-peak price of $0.30 per kWh (both labeled assumptions). The same car drawing 30.8 wall kWh per 100 miles costs about 3.1 cents per mile charged off-peak and about 9.2 cents per mile charged only on-peak, which is within reach of an efficient gasoline car's per-mile cost at the assumed $3.60 per gallon. TOU pricing does not change the car; it changes which version of your electricity price the formula uses. Practically: set the car's charge schedule to the off-peak window, confirm any demand charge rules if your solar export plan uses them, and verify the schedule after any app or vehicle update. A schedule that silently resets to immediate charging is the most expensive settings change a car can make.

One caution travels with TOU savings. Some plans pair low off-peak energy prices with a monthly demand charge based on your highest draw in a window. Charging at full Level 2 power alongside cooking and air conditioning can set that peak. Slower charging across more off-peak hours often costs almost nothing extra in energy and avoids the spike; our EV home charging guide covers matching circuit capacity to how you actually drive.

Worked Examples: Per Mile, Per Month, Per Year

All rates below are labeled assumptions, chosen to be plausible rather than favorable. Swap in your bill and your pump price.

Example 1: Typical suburban commuter. Assumptions: EV at 30.8 wall kWh per 100 miles (rated 28 plus 10 percent losses), home rate $0.16 per kWh, gasoline $3.60 per gallon, gasoline car 32 MPG, 1,000 miles per month.

• EV: 0.308 kWh per mile x $0.16 = 4.9 cents per mile, about $49 per month, about $590 per year.
• Gasoline: $3.60 / 32 = 11.3 cents per mile, about $113 per month, about $1,350 per year.
• Gap under these assumptions: roughly $64 per month, about $760 per year.

Example 2: TOU household charging off-peak. Same car and driving, off-peak rate $0.10 per kWh (labeled assumption).

• EV: 0.308 x $0.10 = 3.1 cents per mile, about $31 per month, about $370 per year.

Example 3: Public fast charging road trip. Public DC fast charging is commonly priced per kWh or per minute at levels set well above home electricity, because the network is selling speed and location, not just energy; our home charging cost guide explains why home charging wins where a car sleeps. Labeled assumption: $0.45 per kWh at the plug, same 30.8 wall kWh per 100 miles adjusted for session losses already included.

• EV: 0.308 x $0.45 = 13.9 cents per mile, briefly above the efficient gasoline car in Example 1. This is normal road-trip economics, not an argument against the car: most miles happen at home rates, and the fast-charging premium applies to the trips where time matters most.

Example 4: Against a hybrid. Gasoline at $3.60 and 45 MPG gives 8 cents per mile. The home-charged EV in Example 1 at 4.9 cents still wins; a TOU household at 3.1 cents wins bigger; an EV charged mostly at the Example 3 public price loses on running cost while keeping the other EV ownership traits. Our broader ownership math, including maintenance and tires, lives in the EV home charging guide hub.

Blending is the honest way to total a year. If 90 percent of your miles charge at home and 10 percent on road-trip fast chargers, weight the per-mile figures by those shares rather than letting either price stand for the whole year. Most drivers find their home share higher than they first guess, because the car starts every day with the range the night provided.

The Same Math in Cost Per 100 Miles

Some drivers think in fill-ups rather than miles, so here is the identical arithmetic at 100-mile scale, using the wall consumption from Example 1 (30.8 kWh per 100 miles, labeled assumption). At $0.10 per kWh, 100 miles cost about $3.08. At $0.16 per kWh, about $4.93. At $0.20 per kWh, about $6.16. At the $0.45 public fast charging assumption, about $13.86. The gasoline equivalents at $3.60 per gallon: a 45 MPG hybrid covers 100 miles for $8.00, a 32 MPG sedan for $11.25, and an 18 MPG truck for $20.00. This table is the same formulas wearing different units; nothing new is assumed anywhere in it.

Two confusions this framing clears up. First, battery size is not consumption. A large battery costs more to fill from empty, but the per-mile cost depends on kWh per 100 miles, not on how many kilowatt-hours the pack holds. A big efficient sedan can cost less per mile than a small inefficient one. Second, range loss is not cost loss: charging more often in winter raises the per-mile cost only through the consumption term, which is why your own trip-computer average, season by season, is the input worth tracking.

Consumption matters as much as price, so here is the sensitivity at the $0.16 home rate used throughout (labeled assumption, losses already included). A slippery sedan drawing 25 kWh per 100 miles from the wall costs 4.0 cents per mile. A typical crossover at 30.8 costs about 4.9 cents. A large electric truck at 45 costs 7.2 cents, still below the 32 MPG gasoline car at the assumed pump price, but close to the 45 MPG hybrid. Efficiency is the one input you choose when you buy the car, which is why kWh per 100 miles deserves the same attention MPG used to get.

Pairing With Solar, and What Solar Owners Should Price

Households with rooftop solar often ask whether charging on solar is free. The honest accounting depends on the export rule. Where exports earn close to retail under net metering, a kilowatt-hour sent to the car instead of the grid gives up nearly a retail credit, so charging on solar costs about what grid charging costs. Where exports are paid at a lower rate, as in California net billing or Arizona's Resource Comparison Proxy, a kilowatt-hour used by the car displaces a retail purchase and only gives up the smaller export payment, so midday charging genuinely beats grid charging. Our charging an EV with home solar guide covers scheduling, sizing, and the export math, and our state solar cost guides cover the export rules themselves.

The formula does not change for solar owners; the price input does. Use the export rate you would have earned as the opportunity cost of a solar kilowatt-hour, blend it with any grid imports by time of day, and the same per-mile arithmetic applies.

Mistakes That Distort the Comparison

• Using the sticker efficiency at the wall. Rated kWh per 100 miles is battery-out energy. Add a charging losses allowance before multiplying by your rate.
• Using an advertised energy-only rate. Delivery, riders, and taxes are part of every kWh you buy. Divide a real bill.
• Quoting someone else's gasoline price. National averages hide regional spread; your station and your car's real MPG are the inputs.
• Letting public charging stand for all miles, or home charging stand for all miles. Blend by where the energy actually comes from.
• Ignoring the plan you are actually on. TOU windows, demand charges, and solar export terms change the effective price more than most car-to-car efficiency differences.
• Forgetting that the comparison scales. Every cent per kWh is worth about a third of a cent per mile at typical consumption. Small rate differences compound quietly over 12,000 miles; small MPG differences do the same on the other side.

Frequently Asked Questions (FAQ)

How do I calculate my EV's cost per mile?

Divide your car's kWh per 100 miles by 100 to get kWh per mile, add a charging losses allowance (this guide uses 10 percent as a planning assumption), and multiply by your delivered electricity rate in dollars per kWh. Example: 28 kWh per 100 miles becomes about 30.8 from the wall, and at $0.16 per kWh that is about 4.9 cents per mile.

How do I calculate a gasoline car's cost per mile?

Divide the price per gallon by the car's real miles per gallon. At $3.60 per gallon and 32 MPG, that is about 11.3 cents per mile. Use the fuel economy your car actually returns, not the window-sticker figure.

What electricity rate should I use?

Your delivered rate: a recent bill's usage-based total divided by the kWh used. Headline generation prices understate what you pay per kWh. The EIA Electric Power Monthly is a reasonable placeholder by state, but your bill is the authoritative input.

Is charging at home always cheaper per mile than gasoline?

At typical home rates and typical car efficiencies, yes, by a wide margin, as the worked examples show. The exceptions are an efficient hybrid compared against a high home electricity rate, or heavy use of public fast charging priced well above home rates. Time-of-use off-peak charging usually restores the gap.

How much do charging losses add?

Enough to matter and not enough to change the conclusion. This guide plans with a 10 percent allowance on top of rated consumption as a labeled assumption; Level 1 charging in cold weather can waste proportionally more than Level 2. Your car's reported consumption over a month is the best correction.

Does solar make charging free?

Not in accounting terms. A solar kilowatt-hour used by the car is one you cannot export. Under 1-to-1 net metering that opportunity cost is close to the retail rate; under lower export rates like California's or Arizona's, self-consumed solar is genuinely cheaper than grid power. Either way, plug the export rate into the formula as the price.

What to Read Next

• EV Home Charging Guide - the hub for setup, safety, and ownership math
• How Much Does It Cost to Charge an EV at Home? - monthly bill math from your own utility bill
• Level 1 vs Level 2 EV Charging - speed, efficiency, and cost tradeoffs
• Charging an EV With Home Solar - export credits, self-consumption, and scheduling
• Time-of-Use Electricity Rates Strategy Guide - charging inside the cheap window
• EV Charger Installation Cost - what the home setup itself costs