MilometryWhy one electric car has three different ranges
Europe, the US and Japan each rate electric range their own way. What the WLTP, EPA and WLTC figures measure, why they disagree, and why none of them is a mileage record.
General information, not advice. Written as general information on 6 November 2026. Details change, so check the official source or a qualified professional before you rely on it. This is not legal, tax or financial advice.
Look up the same electric car on a British, an American and a Japanese website and you can find three different range figures for it. None of them is wrong. Each country rates range with its own laboratory procedure, and the procedures answer slightly different questions.
Europe and the UK: WLTP
In Britain and across Europe the official figure comes from the Worldwide Harmonised Light Vehicle Test Procedure, WLTP. The Vehicle Certification Agency says it replaced the older NEDC procedure in September 2017 and was mandatory for all new petrol and diesel cars by September 2018, with the stated aim of a closer representation of real-world figures than the test it replaced.
The car is driven on rollers in a laboratory through four phases, named Low, Medium, High and Extra-high, which stand in for town, suburban, rural and motorway driving. For an electric car the cycle is repeated until the battery is empty, and the distance covered becomes the quoted range.
The important word is laboratory. The VCA is explicit that the figures are obtained under specific test conditions, and that real results vary with driving style, accessories and extra weight carried.
The United States: the EPA and the 0.7 factor
The US Environmental Protection Agency also tests in a laboratory, on a dynamometer. A fully charged car is driven over the EPA city cycle until the battery is depleted, and the same is done on the highway cycle. Manufacturers can instead run a multi-cycle test that combines four city cycles, two highway cycles and two constant speed cycles.
Then comes the step Europe does not take. The EPA says the most common approach is to multiply the laboratory results, range included, by 0.7, to account for things the test does not reproduce: air conditioning, cold weather, and high speed or aggressive driving. Its own example is a 200 mile highway result in the laboratory becoming a 140 mile highway range. The adjusted city and highway figures are then weighted 55% and 45% to give the single number on the label.
That built in haircut is the main reason an American range figure tends to look lower than a European one for the same car.
Japan: WLTC, reported by road type
Japan uses the WLTC driving cycle from the same international family, which replaced its home grown JC08 test. What Japan added is the way the result is shown. Since a Ministry of Land, Infrastructure, Transport and Tourism announcement on 4 July 2017, catalogues and showroom cars must show a figure for city (市街地), suburban (郊外) and expressway (高速道路) driving alongside the overall WLTC figure, required on new models from October 2018.
The ministry's reason was blunt: it noted reports that real consumption can fall as much as 40% below the catalogue figure, depending on conditions and how the car is driven. The breakdown is there so a buyer can pick the number that looks most like their own driving.
Why they will never agree
Put together, the three figures are measuring three slightly different things:
| System | Where it applies | What the headline figure is |
|---|---|---|
| WLTP | UK and Europe | The laboratory result over four phases, unadjusted |
| EPA | United States | The laboratory result multiplied by 0.7 (most commonly), weighted 55% city and 45% highway |
| WLTC | Japan | The laboratory result, with separate city, suburban and expressway figures beside it |
A buyer comparing an American review with a British brochure is not comparing like with like, and neither figure is a promise. Winter, motorway speed and a full car all pull the real number down, the same way they pull down a petrol car's real MPG.
Why none of this changes a mileage claim
For anyone claiming business mileage, the rated range is simply not part of the calculation. A flat mileage rate pays per mile or kilometre driven, not per mile the battery was rated for. In the UK the approved mileage rate is the same for an electric car as a petrol one; in the US the IRS standard mileage rate does not separate fuel types; and Japan has no national rate at all, so an employer sets its own.
What every one of those systems does need is the distance actually driven, trip by trip, with a date and a purpose. A range figure is an estimate of what a battery might do. A log is a record of what the car did. Only the second one supports a claim, and if you want to know what your electric miles are really costing, it is also the only one that tells you what an electric mile costs in your car.
Sources
- The Worldwide Harmonised Light Vehicle Test Procedure (Vehicle Certification Agency)
- Fuel economy and EV range testing (US Environmental Protection Agency)
- Learn more about the electric vehicle label (fueleconomy.gov)
- 乗用車等の燃費表示に走行環境毎の燃費表示が加わります (Ministry of Land, Infrastructure, Transport and Tourism, 4 July 2017)
General information, not legal or tax advice. Official range and economy figures are test results under laboratory conditions, not a guarantee of what any car will achieve.
