What is an EV tariff?
An EV tariff is an electricity tariff designed around electric car charging, often with cheaper off-peak rates for charging at night.
An EV tariff is an electricity deal aimed at electric vehicle owners. It usually gives cheaper electricity during certain off-peak hours, so you can charge your car for less when demand on the grid is lower.
The important point is that an EV tariff is not just one simple price. Your real cost depends on the off-peak rate, peak rate, standing charge, charging time, vehicle efficiency and whether you can reliably charge during the cheap window.
Why EV tariffs matter
EV tariffs matter because charging at home can be much cheaper than charging publicly, but only if the tariff, charger and car schedule line up properly. A low overnight rate can cut the cost per mile, while a higher daytime rate can make the rest of your household electricity more expensive.
That means the cheapest-looking EV tariff is not always the cheapest overall. You need to compare the car charging saving against the full household bill, not just the headline overnight price.
Estimate your EV charging cost
Use battery size, charge level, price per kWh and charging losses to estimate cost per charge and cost per mile.
How an EV tariff works
Most EV tariffs use time-of-use pricing. You pay one rate during cheaper charging hours and a different rate outside that window. Some deals are designed for overnight charging, while others may offer a limited number of smart-charging hours controlled through an app or charger connection.
EV charging cost = kWh used × electricity price per kWh
Cost per mile = charging cost ÷ miles added
Useful comparison = EV cost per mile vs petrol or diesel cost per mileThe calculation is simple, but the result can change quickly when electricity prices, public charging prices or your car's efficiency changes.
What to compare before choosing an EV tariff
Do not compare EV tariffs using the off-peak unit rate alone. The wider tariff structure matters because your home still uses electricity outside the charging window.
| Tariff feature | Why it matters | What to check |
|---|---|---|
| Off-peak rate | Controls the cost of charging during the cheap window. | How many hours you get and whether they fit your routine. |
| Peak rate | Applies to household electricity outside the cheap window. | Whether daytime electricity becomes more expensive. |
| Standing charge | A daily fixed charge you pay regardless of usage. | Whether a lower unit rate is offset by a higher fixed charge. |
| Smart charging rules | Some deals require a compatible charger, car or app. | Whether your vehicle and charger are supported. |
| Exit fees | Fixed tariffs may charge you to leave early. | Whether you might move, switch supplier or change car soon. |
| Public charging need | Public charging can cost more than home charging. | How often you need rapid or destination charging away from home. |
Current UK context
For July to September 2026, Ofgem's domestic energy price cap period includes an average Direct Debit electricity unit rate of 26.11p per kWh, but this is not the same as every EV tariff or every region. Actual rates vary by supplier, region, meter type and whether you are on a fixed, standard variable or specialist EV deal.
GOV.UK's advisory electric rates for fully electric company cars from 1 June 2026 are 7p per mile for home charging and 15p per mile for public charging. Those figures are useful context, but they are HMRC advisory rates, not a guarantee of your personal charging cost.
Worked example
Suppose your EV adds 40kWh from the wall overnight and your off-peak EV tariff rate is 9p per kWh.
40kWh × £0.09 = £3.60
If the charge adds 140 miles:
£3.60 ÷ 140 = 2.57p per mileIf the same charge used a 26.11p/kWh standard-rate assumption, it would cost £10.44 before considering whether your tariff has different standing charges or daytime rates.
EV tariff vs public charging
An EV tariff mainly helps when you can charge at home. If you rely heavily on public rapid chargers, your cost per mile may be much higher than a home-charging example suggests.
- Home EV tariff: usually best for regular overnight charging at your own property.
- Standard domestic tariff: simpler, but may be more expensive per charge if you cannot access a cheap window.
- Public charging: convenient for long journeys or drivers without home charging, but often costs more per kWh.
- Workplace charging: may be cheaper or free, but depends on employer policy and availability.
Common mistakes
FAQs
Is an EV tariff always cheaper?
No. It depends on how much you charge at home, how often you can use the cheap window, and whether the tariff increases your normal household electricity costs.
Do I need a smart meter for an EV tariff?
Many EV tariffs require a smart meter because the supplier needs to measure usage at different times of day. Some smart-charging tariffs may also require a compatible charger, car or app.
What is a good EV tariff rate?
A good rate depends on the market at the time and your charging pattern. Compare the off-peak unit rate, peak unit rate, standing charge, contract length and exit fees before deciding.
Should I use the price cap rate in an EV calculator?
You can use it as a rough benchmark, but your own tariff rate is better. EV tariffs, fixed deals and public chargers can be very different from the national price-cap average.