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EV Direct Debit estimator: your monthly bill on an EV tariff

Rates last checked: 15 October 2026 · PlugLater

Pick a tariff, enter your home use and driving, and see roughly what a monthly Direct Debit would be: the units plus the standing charge, spread over 12 months. The 13 tariffs are the ones on our EV tariff comparison, with regional rates for Octopus.

Rates last checked: 15 October 2026. Tariffs from UK EV tariffs compared. Where a supplier only gives a day rate or standing charge in a quote, the box is left empty for you to fill in.

EV tariff Octopus region

Rates (p/kWh, p/day) Off-peak rate Day rate Standing charge (p/day)

Your usage Home use without the car (kWh a year) EV miles a year Efficiency (miles per kWh) Share of charging done off-peak (%)

–

Units a year: –
Standing charge a year: –
Total a year: –
Electricity: –

An estimate only. Check with your supplier: they set your Direct Debit from your meter readings and may hold extra in winter or add a buffer.

How it works: car kWh = miles ÷ miles per kWh. The off-peak share is billed at the off-peak rate and the rest at the day rate. Home use is billed at the day rate (a conservative choice; if you run appliances overnight it will be a little lower). Add 365 days of standing charge and divide the year by 12. No charging losses, no credit or debt on your account.

Example

2,500 kWh of home use and 8,000 miles at 3.61 miles per kWh (2,216 kWh for the car), all charging off-peak, London: about £102 a month on Intelligent Octopus Go, against about £120 a month on the Ofgem price cap. Worked example, not an average.

Next: is an EV tariff worth it? quick check · whole-bill EV tariff savings calculator.

Questions people ask

How is my EV Direct Debit worked out?

Suppliers estimate a year of use from your meter readings, price it at your tariff’s rates plus the standing charge, and usually spread it over 12 months. This estimator does the same arithmetic with your inputs. Your supplier’s figure can differ because of account balance, seasonal use and its own buffer.

Will my Direct Debit go up when I get an EV?

Usually yes, because you use more electricity in total, even if each car kWh is cheap. Ask your supplier to review it once you have a month or two of readings with the car.

Why is the Direct Debit the same every month when winter costs more?

Most suppliers spread the yearly cost evenly. You build up credit in summer and use it in winter.

Why are some boxes empty?

Some suppliers only give a day rate and standing charge in a postcode quote. We leave those boxes empty rather than guess.

Not financial advice. This is an estimate from published rates and your inputs, not a bill. Check your own quote, bill and the supplier’s or manufacturer’s current terms before you switch or buy anything.

Sources

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