The cost of charging depends on where you buy electricity and how much energy you need for the miles you drive. A cheap overnight unit rate helps only if you can use its charging window and the rest of the household bill remains competitive.
Start with the electricity you pay for
For a reliable running-cost record, divide the total cost of charging over a period by the miles driven in that period. Use charger receipts or a dedicated meter where possible, and compare periods with similar starting and finishing battery levels. Dashboard consumption can exclude charging losses and other electricity taken from the supply.
If your efficiency is stated in miles per kWh, electricity required for 100 miles is 100 divided by miles per kWh. If that efficiency measures energy leaving the battery, allow separately for supply-to-battery losses. Do not mix kWh per 100 kilometres with kWh per 100 miles. The earlier article did so, understating costs.
Home charging: compare the whole tariff
Ofgem's price cap applies to eligible default domestic tariffs; it is not a fixed annual bill or a universal EV charging price. Unit rates and standing charges vary with region and payment arrangements. Use the current period in Ofgem's unit-rate tables and your supplier's actual quote.
For a time-of-use offer, record the cheap window, daytime price, standing charge, eligibility and compatible equipment. Estimate how much charging fits within that window. Add the cost of the household electricity used outside it. A saving on the car can be offset elsewhere on the bill.
Workplace and public charging
| Location | What to check |
|---|---|
| Workplace | Employee price, access days, booking rules and whether spaces are reliably available |
| Public AC | Energy price, parking charges, time limits and the car's AC charging capability |
| Public DC | Price at that site, membership terms, idle fees and payment method |
Calculate a membership's value from the energy you expect to buy on that network. Include the subscription in the total. A national brand name does not establish the price at a particular charger or through a roaming app.
Build your own annual charging mix
Split expected purchased energy between home, work and public charging. Multiply each amount by its applicable price, then add subscriptions, incremental parking costs and other session fees. Keep installation costs separate so you can spread them over your intended ownership period.
For petrol comparisons, use the correct UK imperial-mpg conversion and a fuel price from the same period. Compare energy costs first, then add depreciation, insurance, finance, tax and maintenance for the full ownership budget.
The old operator price league table has been removed because its prices and assumed consumption could not support a current comparison. Before choosing an EV without home charging, check the actual stations near your regular destinations and the terms shown at payment.