One of the most common questions from prospective EV buyers is simple: how much does it actually cost to charge an electric car? The answer depends enormously on where you charge. Home charging on a standard tariff, a smart overnight rate, the office car park, or a motorway rapid charger can vary by a factor of ten to one. This guide cuts through the confusion with real 2026 figures.
The Baseline: Petrol for Comparison
At the time of writing, unleaded petrol averages 142p per litre across the UK (RAC Fuel Watch, March 2026). A typical family petrol car returning 40 mpg (7.06 l/100km) therefore costs about £10.03 per 100 miles in fuel alone. Diesel at 148p/litre and 50 mpg works out to £8.60 per 100 miles. These are the benchmarks against which we compare every charging option.
Home Charging: The Gold Standard
Standard tariff (Ofgem price cap)
The Ofgem energy price cap for Q1 2026 sits at 24.5p per kWh. A typical EV such as the Tesla Model 3 consumes approximately 18 kWh per 100 miles (around 4.5 miles/kWh on real-world driving). That gives a home charging cost of:
18 kWh × 24.5p = £4.41 per 100 miles
That is less than half the cost of petrol. For a driver covering 10,000 miles a year, the annual fuel saving versus petrol is around £562.
Economy 7 / overnight tariffs
Economy 7 tariffs offer cheaper electricity during off-peak overnight hours (typically midnight to 7am). Overnight rates average around 12p/kWh, dropping your charging cost to:
18 kWh × 12p = £2.16 per 100 miles
At this rate, driving 10,000 miles a year in electricity costs just £216 - roughly the cost of three fill-ups in a petrol car.
Octopus Agile
Octopus Agile is a dynamic tariff that adjusts its price every 30 minutes based on the wholesale electricity market. Savvy EV owners who charge during cheap periods (often between 11pm and 6am) typically pay around 18p/kWh on average, with prices occasionally going negative (you get paid to use electricity). Average cost: roughly £3.24 per 100 miles.
Octopus Go
Octopus Go provides a flat overnight rate of around 7.5p/kWh (between midnight and 5am), with standard rates the rest of the day. If you can schedule your charging for those hours, your cost falls to a remarkable £1.35 per 100 miles.
Workplace Charging
Many employers provide free or subsidised charging as part of green travel initiatives. HMRC currently allows tax-free workplace charging for employees - a valuable perk worth up to several hundred pounds per year. Where a fee is charged, typical workplace AC rates (7–22 kW) run from 15–25p/kWh, comparable to a good home tariff.
Public AC Charging
Public AC chargers (7–22 kW, typically 2–8 hours for a full charge) are found at supermarkets, car parks, and high streets. Pricing varies widely:
- Pod Point (Tesco, ASDA): free at many locations, or ~40–45p/kWh
- Osprey: ~50p/kWh
- Ubitricity (lamp-post chargers): ~44p/kWh
At 45p/kWh, charging 100 miles costs £8.10 - still cheaper than petrol but the gap narrows considerably.
Public DC Rapid and Ultra-Rapid Charging
DC rapid chargers (50–350 kW) can add 100+ miles in 20–30 minutes. They are the most convenient but also the most expensive way to charge.
| Network | Price per kWh | Cost per 100 miles |
|---|---|---|
| Tesla Supercharger (non-Tesla) | 46p | £8.28 |
| BP Pulse (rapids) | 69p | £12.42 |
| InstaVolt | 79p | £14.22 |
| Gridserve Electric Highway | 79p | £14.22 |
| Osprey (ultra-rapids) | 85p | £15.30 |
At the upper end - InstaVolt or Osprey ultra-rapids - charging costs more per mile than petrol. This is why EV economics depend so heavily on having access to home charging or a good workplace scheme. If you rely primarily on public rapids (for example, if you live in a flat without a dedicated parking space), the fuel-cost advantage largely disappears.
Full Comparison Table
| Charging / Fuel Type | Rate | Cost/100 miles | Annual cost (10k mi) |
|---|---|---|---|
| Octopus Go (EV overnight) | 7.5p/kWh | £1.35 | £135 |
| Economy 7 night rate | 12p/kWh | £2.16 | £216 |
| Octopus Agile (avg) | ~18p/kWh | £3.24 | £324 |
| Ofgem cap (home standard) | 24.5p/kWh | £4.41 | £441 |
| Public AC (Pod Point avg) | 40p/kWh | £7.20 | £720 |
| BP Pulse rapid DC | 69p/kWh | £12.42 | £1,242 |
| InstaVolt rapid DC | 79p/kWh | £14.22 | £1,422 |
| Petrol (142p/L, 40mpg) | 142p/L | £10.03 | £1,003 |
Installing a Home Charger
A dedicated 7 kW home wallbox (from providers such as Ohme, Zappi, or Pod Point) costs approximately £800–1,200 installed. The OZEV Electric Vehicle Chargepoint Grant provides up to £350 off the cost of a home charger for eligible customers in flats and rented accommodation. Homeowners in houses may qualify through certain energy companies or local authority schemes.
Without a home charger, you're relying on a standard 3-pin plug (2.3 kW) which is slow - a full charge from empty takes 20+ hours - and not recommended for daily use.
The Bottom Line
If you have access to home or workplace charging, an EV can be significantly cheaper to run than a petrol car. If you rely entirely on public rapids, the economics are far less compelling. The key question to ask yourself before buying an EV is not "what's the cheapest tariff?" but "where will I charge most of the time?"
Use our charging cost calculator to model your specific situation - including your home tariff, typical public charging usage, and annual mileage - and see your true annual charging bill.
Sources: Ofgem energy price cap Q1 2026, RAC Fuel Watch March 2026, BP Pulse pricing March 2026, InstaVolt pricing March 2026, Gridserve pricing March 2026, Octopus Energy published tariffs, DVLA OZEV grant scheme. Electricity consumption based on Tesla Model 3 Long Range real-world data (Spritmonitor.de, EVDB). All prices correct as at March 2026.