Miles per kWh Explained
By AlexGuide overview:
- Miles per kWh measures how far an electric car travels on one unit of electricity. It's the EV equivalent of miles per gallon.
- The higher the figure, the more efficient the car. A good miles per kWh for a modern electric car is 4.0 or above.
- Official figures don't always reflect real-world driving. Weather, speed, and temperature can all affect how efficient your car actually is.
- If you're leasing an electric car, miles per kWh directly affects your running costs and it's worth checking before you sign your contract.
Miles per kWh is one of the most misunderstood figures in the electric car world, and one of the most useful.
Think of it as the EV equivalent of miles per gallon. It tells you how far your car will travel on a single unit of electricity, and the higher the figure, the less you'll spend on charging.
If you're considering leasing an electric car, it's worth understanding before you sign. This guide explains everything you need to know about miles per kWh, including what it is, what a good miles per kWh is, and a few models to look out for.
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Miles per kWh tells you how many miles an electric car will travel on one unit of electricity, which is essentially how efficient it is. The higher the number, the more efficient the car.
A typical figure looks something like this: 4 miles/kWh, meaning the car uses one unit of electricity for every four miles driven.
Some manufacturers flip this around and show it as kWh per 100 miles instead. For example, 25 kWh per 100 miles means the car used 25 units of electricity to travel 100 miles.
They're just testing your maths skills! Don't worry, both miles per kWh and kWh per 100 miles mean the same thing.
“Miles per kWh is really a straightforward measure of how hard your car works for every unit of electricity it uses. Once you understand it, comparing electric cars becomes a lot easier.”
The official method is straightforward: fully charge the car, drive it until the battery is flat, then measure how much electricity it takes to charge it back up. That gives you the official miles per kWh figure.
If you want a rough estimate, divide the car's stated range by its battery size.
- 300 mile range / 60kWh battery = 5 miles/kWh
The higher the miles per kWh, the better. You want to travel as far as possible while using as little energy as possible.
Miles per kWh | What it means |
|---|---|
5+ miles/kWh | Excellent - among the most efficient EVs available |
4-5 miles/kWh | Very good - this is where most modern EVs sit |
3-4 miles/kWh | Decent - still reasonable for everyday driving |
Below 3 miles/kWh | Poor - more common in older or larger EVs |
We'd recommend setting your minimum at 3 miles/kWh. Anything below that and you'll notice it in your running costs.
If your manufacturer uses the kWh per 100 miles format, here's how to interpret it:
- Under 20 kWh/100 miles - very efficient
- 20-30 kWh/100 miles - average for most modern EVs
- Over 30 kWh/100 miles - less efficient
A lower kWh per 100 miles is better.
Miles per kWh is different from miles per gallon, but there's a way you can compare electric cars to traditional cars.
The 'multiply by 40' rule gives you a rough estimate of converting miles per kWh into MPG. For example, if a car has 4 miles per kWh, that's equivalent to 160 MPG. Not bad at all!
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Like MPG, there are various factors that affect miles per kWh, including the conditions, road quality, and driving habits. Your actual efficiency will very depending on:
- Temperature - Cold weather is the biggest factor. Batteries lose efficiency in low temperatures, and heating the cabin draws extra power.
- Speed - Motorway driving at 70 mph uses significantly more energy than town driving at 30 mph.
- Air conditioning and heating - Both drain the battery faster than most people expect.
- Road type and gradient - Hills use more energy. Stop-start city driving is actually more efficient for EVs than it is for petrol cars, thanks to regenerative braking.
- Load - Under-inflated tyres or a full boot impact efficiency, just as they would in any car.
Use official figures at a guide, not a guarantee. For a realistic expectation, it's worth reading owner reviews and independent road tests for any car you're considering.
Figures based on official WLTP data. Real-world efficiency will vary depending on speed, temperature, and driving style.
Both range and miles per kWh need to be considered, but personal preference also comes into play.
Prioritise miles per kWh if:
- You mostly drive short distances or commute locally
- You can charge at home overnight
- Keeping running costs as low as possible is a priority
Prioritise range if:
- You regularly drive long distances or take motorway journeys
- You live somewhere with limited public charging
- You want the flexibility to travel without planning every stop
The two aren't mutually exclusive. A more efficient car will likely stretch its range further, but knowing which is your bigger priority will help you narrow your shortlist.
If you're looking for an electric car, check out all our latest electric car lease deals. Nationwide Vehicle Contracts is one of the UK's largest car leasing brokers and offers a range of electric lease deals to suit your every need.
We also produce various electric car leasing guides to help you out, such as the Benefits of an Electric Car and Electric Car Charging Costs.
Guide Information
Originally published: 4th October 2023
Last updated: 1st April 2026
Due to be reviewed: 1st April 2027
