If you take one thing from everything written about running an electric car cheaply, take this: the tariff you put it on matters far more than the car you buy. A dedicated EV tariff gives you a block of cheap electricity in the small hours, currently as low as around 5.5p a unit against a standard rate near 26p, and charging in that window is what turns an electric car into the cheapest thing on the road to fuel. Here is how these tariffs work and how to choose one.
The short answer. A dedicated EV tariff gives you a cheap overnight window, often around 5.5p to 9p a unit against a standard rate near 26p, for charging the car and running the house in the small hours. The savings dwarf anything to do with the car. You need a smart meter to get one, and the tariffs differ mainly on how long the cheap window is, how deep the discount goes, and whether they control the charging for you.
What an EV tariff is
An EV tariff is a kind of time-of-use tariff, meaning the price you pay per unit changes with the time of day rather than staying flat. The defining feature is a block of very cheap hours overnight, typically something like five or six hours in the small hours, when demand on the grid is low and suppliers want to soak up cheap overnight generation. Set your car to charge in that window and you buy its energy at a fraction of the normal price. It is the same idea as the older Economy 7 night-rate tariffs, brought up to date for electric cars and made far more flexible by the smart meter. An EV tariff is one specific kind of time-of-use tariff, tuned for charging a car overnight.
How cheap the cheap rate now is
The overnight rates have fallen sharply. The best-known dedicated EV tariffs now offer off-peak rates around 5.5p per kWh, with some regions seeing rates even lower, against a standard price-cap rate of about 26p. Against that 26p, paying 5.5p to charge is roughly a fifth of the price, which is why the saving is so large. The exact figure varies by supplier and by region, since the cost of delivering electricity differs across the country, so the rate on offer at your postcode is what counts.
| Rate | Typical price per kWh | Cost per mile |
|---|---|---|
| EV tariff, off-peak overnight | ~5.5p to 9p | ~1.6p to 2.6p |
| Standard single rate (price cap) | 26.11p | ~7.5p |
| EV tariff, daytime peak | ~30p or more | ~8.6p or more |
Cost per mile at about 3.5 miles per kWh. Off-peak EV rates and the standard cap rate are mid-2026 figures; both vary by region. The daytime rate on an EV tariff is higher than the flat standard rate, which is the trade-off explained below.
Two flavours: fixed window and smart managed
Dedicated EV tariffs come in two broad types. The simpler kind gives you a fixed cheap window, say half past eleven at night to half past five in the morning, during which all your electricity is at the low rate; you set the car or the charger to draw power then. The smarter kind hands control to the supplier, who talks to your car or charger and fills it during the cheapest hours of the night on your behalf, sometimes spreading the charge to catch the very lowest prices and often guaranteeing the cheap rate even if the car charges slightly outside the usual window. Either works; the managed type takes the thinking out of it, while the fixed-window type gives you simple, predictable hours to schedule against.
The catch: the daytime is dearer
An EV tariff is not free money, and the trade-off is important. In exchange for the cheap overnight block, the daytime or peak rate is usually higher than the flat standard rate you would otherwise pay. That means the tariff only saves you money if you genuinely shift your heavy use, above all the car charging, into the cheap window, and avoid running big loads at the expensive peak. For a household that charges the car overnight and is careful about when it runs the dishwasher, washing machine and so on, the saving is large. For one that ignores the windows and uses power heavily through the dear daytime, an EV tariff can cost more than a standard one. The whole game is using the cheap hours and dodging the dear ones.
What to compare between tariffs
When you weigh up EV tariffs, look past the headline off-peak rate at three things. First, how long the cheap window is, since a longer window gives you more time to charge and to run other loads cheaply. Second, how big the gap is between the cheap and the peak rates, because a deep discount overnight paired with a punishing daytime rate may not suit you if you cannot avoid daytime use. Third, whether the tariff controls the charging itself or leaves it to you, which matters if you would rather not set schedules by hand. A tariff that pairs a long, very cheap window with a daytime rate you can live with is the one to want.
Beyond the car: the whole house benefits
The cheap window is not just for the car. During those hours your whole home is on the low rate, so it pays to shift other heavy, flexible loads into the night as well: run the dishwasher and washing machine on a timer to finish overnight, heat water with an immersion in the cheap hours, and charge anything else hungry then too. Done well, an EV tariff quietly lowers a good chunk of the household bill, not only the motoring, which is part of why getting a smart meter and moving onto one is close to essential for an electric-car household.
The bottom line
A dedicated EV tariff is the single biggest lever on what an electric car costs to run, giving you overnight electricity at around 5.5p to 9p a unit against a standard rate near 26p, with the car set to drink in that window. The price is a dearer daytime rate, so the tariff rewards shifting your heavy use into the cheap hours and punishes ignoring them. Get a smart meter, pick a tariff with a long, deep cheap window you can actually use, charge the car and run the house overnight, and the savings far outstrip anything the choice of car could deliver.