Why Is My Electric Car Getting Fewer Miles Than Advertised?

You bought an electric car advertised at 280 miles, and in real life you are seeing closer to 220. It is one of the most common worries among EV owners and buyers, and it usually comes with a nagging question: is something wrong with the battery, or is this just how it is?

The short answer is that a gap between the advertised range and what you actually get is normal, expected, and true of almost every EV on the road. The advertised number was never a promise. But there is a point where a gap stops being normal and starts pointing at a real problem, and knowing the difference is what this guide is about.

The advertised number is a lab figure, not a real journey

Every EV sold in the UK and Ireland quotes a WLTP range. WLTP stands for Worldwide Harmonised Light Vehicle Test Procedure, and the key thing to understand is that it is a laboratory test, not a measurement of real driving.

The test is run at a mild temperature of around 23°C with the climate control switched off, on rollers rather than a real road, at an average speed of under 30mph. It is designed to be repeatable and to let you compare one car against another on a level playing field. It was never designed to predict what you personally will get on a wet motorway in February with the heater on.

Because the conditions are so gentle, the WLTP figure sits at the optimistic end of what is achievable. Real UK driving typically delivers somewhere around 78% to 85% of the WLTP number (Motability). In other words, a shortfall of roughly 15% to 22% against the sticker is completely ordinary. Independent fleet testing has found EVs falling short of WLTP by around 15% on average (Fleet News). We explain the test itself in more detail in what WLTP range actually means.

Why the gap gets bigger in certain conditions

The 78% to 85% figure is a general average. Two situations push the gap wider, and both are perfectly normal.

Motorway driving

The single biggest surprise for new EV owners is how much motorway cruising eats into range. Because the WLTP test averages under 30mph, sustained driving at 70mph uses far more energy than the lab figure assumes. At motorway speeds you can typically expect 20% to 30% below the WLTP number. This is physics, not a fault. Air resistance climbs sharply with speed, so a steady 70mph run will always return fewer miles than the same battery would give around town.

Cold weather

Winter is the other big one. In a UK winter it is typical to see a 20% to 40% drop against WLTP. Batteries are chemical, and cold chemistry delivers less energy. On top of that the car spends power heating the cabin, and sometimes heating the battery itself. To put real numbers on it, a Tesla Model 3 in a UK winter realistically returns around 170 to 210 miles for the Standard Range and 220 to 270 miles for the Long Range (CarBuyerIQ), well below its headline figure. That is not a failing battery, it is January. We go through this properly in why EV range drops in winter.

The important feature of cold-weather loss is that it comes back. When the weather warms up, so does your range. That single fact is the key to telling a normal gap from a real one.

Other everyday reasons your range looks short

Before worrying about the battery, it is worth ruling out the ordinary stuff:

• How you drive. Hard acceleration, hilly routes, and headwinds all cost range.
• What you are carrying. A full car, a loaded boot, or a roof box adds weight and drag. A roof rack in particular takes a bigger bite than most people expect.
• The dashboard estimate itself. The range display is a prediction based on your recent driving, not a fixed measurement. A few motorway runs will drag it down, a few gentle town trips will push it back up. This can look like the battery changing when nothing about the battery has changed at all.

So how much shortfall is normal?

Put it all together and a healthy used EV can easily show:

• Around 15% to 22% below WLTP in ordinary mixed driving.
• 20% to 30% below on a motorway run.
• 20% to 40% below in cold winter conditions.

If what you are seeing fits inside those bands, and it lines up with the weather or the type of journey, your battery is almost certainly fine. A car that quietly loses range in winter and recovers it in spring is behaving exactly as it should.

When a gap points to a real battery problem

Here is the pivot. A normal shortfall tracks the conditions. A battery problem does not.

The clearest warning sign is a shortfall that persists in mild weather and does not recover. If your usable range in a comfortable 15°C to 20°C spring or summer is clearly worse than it was in the same conditions a year ago, that is a more meaningful signal than any bad week in January. Seasonal loss returns. Genuine degradation does not.

The second thing to weigh is the size of the gap against the car's age and mileage. Some capacity loss over the years is normal and expected, and we cover the typical curve in how used EV battery degradation works. A modest, gradual decline fits the pattern. A large shortfall well beyond the percentages above, on a car that is not especially old or high-mileage, does not. That is the combination worth investigating.

There are other clues too, such as charging that behaves differently than it used to, range that swings around unpredictably, or warning messages on the dash. We go through the full list in the signs of a failing EV battery.

Why you cannot settle this by feel

Notice the problem. Almost every symptom of a bad battery also has a completely innocent explanation, and almost every innocent explanation can occasionally hide a real one. Short range might be the motorway, the cold, a roof box, or genuine degradation. You cannot tell which by watching the dashboard, and neither can a general mechanic without the right equipment.

That is why so many buyers refuse to take the number on trust. 88% of used EV buyers say they want an independent battery health assessment before they buy (Startline Motor Finance Used Car Tracker, August 2025). The advertised range, the dashboard percentage, and a seller's reassurance are all estimates. None of them measures the actual condition of the pack in front of you.

The one way to get a straight answer

If you want certainty rather than guesswork, the answer is to have the battery measured directly. A proper test reads the pack itself, rather than trusting the car's own estimate, and tells you the true State of Health along with whether individual cells are weak or out of balance. That is the difference between a range figure that moves with the weather and a verified diagnosis of this exact car, which is exactly why an independent test beats a seller's reassurance.

A short range figure on its own is rarely cause for alarm. But if the gap does not fit the weather or the journey, stop wondering. A £100 certified battery test reads the pack directly and tells you precisely where your battery stands, so you can make decisions with real information instead of a guess.