How Much Does an EV Cost per Mile: The Formula, a Worked Example and Tables

The question behind how much does an ev cost per mile is really two smaller questions: what does each car use per mile, and what does that energy cost where you buy it. Answer those two and the comparison is arithmetic. This page answers them in order, states the assumptions openly, and then shows the result at several annual mileages so you can see how the answer scales. Where the page leaves something out — purchase price, depreciation, insurance, servicing and tax — it says so by name.

The short answer is that the comparison comes down to cost per mile: the petrol car burns US gallons, so its cost per mile is the price per gallon divided by its MPG, while the EV uses kilowatt-hours, so its cost per mile is the electricity price per kWh divided by its miles per kWh. With the example assumptions on this page — petrol at $3.85 per US gallon, 35 US MPG, electricity at 28 cents per kWh and 4.0 miles per kWh — the petrol car costs about $0.11 per mile and the EV about $0.07 per mile. Those are example figures, not prices you should quote, and the rest of this page shows how they were reached and what would change them.

how much does an ev cost per mile: Assumptions used on this page

For how much does an ev cost per mile, the point is this: Every figure in the tables below comes from this assumptions table. Each one is an assumption or an example, not a measured fact about any particular car or a current price. Substitute your own numbers and the method still works.

Input Value used Status
Petrol price $3.85 per US gallon Example price
Petrol efficiency 35 US MPG Assumption
Electricity price 28 cents per kWh Example price
EV efficiency 4.0 miles per kWh Assumption
Annual mileage 10,000 miles Example

How the EV versus petrol comparison works for how much does an ev cost per mile

Taking how much does an ev cost per mile as the case in point: Hold the mileage constant and price the energy each car actually uses. For the petrol car, cost per mile equals the price per gallon divided by its MPG. For the EV, cost per mile equals the price per kWh divided by its miles per kWh. Multiply each cost per mile by the annual mileage and you have the annual fuel and charging bill for each car; subtract one from the other and you have the saving, or the extra cost, under those assumptions. The method is deliberately simple, because a simple method with honest inputs beats a complicated model built on guessed ones. The two numbers that matter most are the electricity price and the petrol car's MPG: a driver who charges at home on a cheap overnight rate will see a very different answer from a driver who relies on public rapid chargers, and a thirsty petrol car widens the gap while an efficient one narrows it.

how much does an ev cost per mile: Worked example: the same distance, two energy bills

Take a driver covering 10,000 miles a year. The petrol car does 35 MPG and petrol costs $3.85 per gallon as an example price, so its cost per mile is $3.85 ÷ 35 = $0.11, and 10,000 miles cost $1,100.00 a year. The EV does 4.0 miles per kWh and electricity costs 28 cents per kWh as an example price, so its cost per mile is $0.28 ÷ 4.0 = $0.07, and 10,000 miles cost $700.00 a year. The difference on fuel and charging alone is $400.00 a year in the EV’s favour under these assumptions. Now change one input and watch the answer move: if the EV is charged mostly at a public rapid charger at, say, double the home electricity price used here, its annual charging cost doubles and most of the saving disappears. If the petrol car is driven mainly in town at lower MPG, the petrol bill rises and the saving grows. That sensitivity is the real lesson — the answer is only as solid as the assumptions, so write yours down before you believe the result.

how much does an ev cost per mile: Cost at different annual mileages

The table uses the worked-example assumptions above — petrol at $3.85 per gallon (example), 35 MPG, electricity at 28 cents per kWh (example), 4.0 miles per kWh. The gap grows with mileage, which is why high-mileage drivers see the biggest fuel-cost difference and low-mileage drivers see the smallest.

Annual miles Petrol cost per year EV charging cost per year Difference
6,000 $660.00 $420.00 $240.00
8,000 $880.00 $560.00 $320.00
10,000 $1,100.00 $700.00 $400.00
12,000 $1,320.00 $840.00 $480.00
15,000 $1,650.00 $1,050.00 $600.00
20,000 $2,200.00 $1,400.00 $800.00

how much does an ev cost per mile: Cost per mile and per 100 miles

At the example assumptions, the petrol car costs $0.11 per mile ($11.00 per 100 miles) and the EV costs $0.07 per mile ($7.00 per 100 miles). Per 100 miles is often the easier figure to compare with a fuel receipt or a charging bill, because both are usually priced in round numbers per hundred miles of driving. If you know your own MPG and your own prices, the same two divisions give your own figures: fuel price per gallon divided by MPG, and electricity price per kWh divided by miles per kWh.

What the comparison leaves out — and why it matters for how much does an ev cost per mile

On this page, how much does an ev cost per mile is the case in point: The fuel and charging maths on this page is only one slice of the real cost. Left out, by design, are the purchase-price gap between the two cars, depreciation, insurance, servicing, tyre wear and tax — every one of them differs between an EV and a petrol car and every one of them moves the true answer. The page also prices electricity at a single rate, while real life mixes cheap overnight home charging with dear public rapid charging; that mix usually matters more than the headline rate. Price your own mix honestly before deciding which car is cheaper for you.

how much does an ev cost per mile: Common mistakes

  • Taking how much does an ev cost per mile as the case in point: Using the same electricity price for every charge hides the real cost. A driver who mixes home and public charging has two different prices, and averaging them into one number without weighting by how much energy comes from each is a common error.
  • Treating the example prices on this page as current prices is the last mistake. Fuel and electricity prices move constantly, so always substitute the prices you actually pay before trusting any saving. That is the point this page works through for how much does an ev cost per mile.
  • Forgetting that winter changes EV efficiency is easy to miss. Cold weather reduces an EV's miles per kWh noticeably, so a saving calculated on summer figures will overstate the winter result. That is the point this page works through for how much does an ev cost per mile.
  • For how much does an ev cost per mile, the point is this: Using one tank or one charge instead of an average is next — a single fill is noisy, and a pump that clicks off early can add a phantom gallon, while a single charge says nothing about your usual mix of home and public charging.

how much does an ev cost per mile: Related calculations

If this page answered your question, these pages take the next step — the same method applied to a closely related question, or the calculator that does the arithmetic for you. That is the point this page works through for how much does an ev cost per mile.

how much does an ev cost per mile: Putting your figure to work

Putting the figure to work is where the method pays off. Once you know your own cost per mile for each car, measured with your own prices and efficiencies, you can price any journey before you set off and compare cars honestly, because you are comparing measured figures rather than brochure claims. Keep a simple log — date, miles, energy used, price paid — and review it monthly. Patterns show up quickly: a winter dip in EV efficiency, a motorway improvement, a slow rise in your charging cost that points to more public charging than you planned. The log turns a vague feeling about fuel use into a number you can act on, and that is the whole point of measuring in the first place. That is the point this page works through for how much does an ev cost per mile.

Frequently asked questions

What is excluded from the EV versus petrol comparison?

Taking how much does an ev cost per mile as the case in point: Purchase price, depreciation, insurance, servicing, tyre wear and tax. This page compares fuel and charging costs only, and says so, because a break-even figure that hides those costs is not a like-for-like comparison. Add them with stated assumptions if you want a total-cost answer.

Does an EV cost more to insure?

For how much does an ev cost per mile, the point is this: Insurance is not part of the fuel-and-charging maths on this page, and it can differ between an EV and a petrol car for reasons that have nothing to do with energy: repair costs, parts availability and the car's value all play a part. Get a quote for both cars before comparing total costs.

What does miles per kWh mean?

It is the EV equivalent of MPG: how many miles the car travels on one kilowatt-hour of electricity. Higher is more efficient. Divide the electricity price per kWh by miles per kWh to get the EV's cost per mile, in the same way you divide the fuel price per gallon by MPG for a petrol car. That is the point this page works through for how much does an ev cost per mile.

How sensitive is the saving to the electricity price?

For how much does an ev cost per mile, the point is this: Very sensitive. Doubling the electricity price doubles the EV's charging cost per mile, while the petrol side is unchanged. That is why this page states its example prices openly: change the electricity price to the one you actually pay and the saving changes with it, sometimes by enough to change the conclusion.

Is an EV always cheaper to run than a petrol car?

Taking how much does an ev cost per mile as the case in point: Not always. On fuel and charging alone, an EV is usually cheaper per mile when it charges mostly at home at an example electricity price, but the answer flips if it relies on expensive public rapid charging or if the petrol car is very efficient. Purchase price, depreciation, insurance and servicing are not in the fuel-cost maths, so a full comparison has to include them before calling either car cheaper overall.