EV Tariff Comparison: UK Overnight & Smart Tariffs in 2026

What makes a tariff an "EV tariff"?

Despite the name, most so-called EV tariffs are really just overnight or time-of-use tariffs with a cheap off-peak window, usually somewhere between four and eight hours long, sat against a higher day rate. They were originally designed to encourage EV owners to charge overnight when demand on the grid is lower, but the underlying mechanic — cheap window, expensive rest-of-day — is exactly the same mechanic that makes a home battery worthwhile.

Two broad types exist. Fixed-window tariffs give you the same off-peak hours every night, published in advance, and work with any smart meter. Dynamic or 'smart' tariffs, like Octopus Intelligent Go, use a connected EV or smart charger to shift your charging into whichever hours are cheapest that night, which can be more efficient but ties the discount to the vehicle rather than the household.

Rates change — always check the supplier's current pricing. Correct as of July 2026. Everything in this article describing rates uses illustrative bands, not live figures, because tariff pricing is updated by suppliers frequently and we don't want to quote you a number that's gone stale by the time you read it.

Why the off-peak window matters

The length and timing of the cheap window shapes what you can realistically do with it. A short window (four to five hours) is fine for charging an EV overnight, but on its own it won't cover a full day of household electricity use unless you're storing the cheap energy somewhere. A longer window (six to eight hours, or more with some dynamic tariffs) gives more flexibility, but usually at a slightly higher off-peak rate as a trade-off.

This is where the difference between 'just charging a car' and 'running a battery' starts to matter. An EV's battery only needs topping up a few times a week. A home battery, sized for daily household use, wants filling every single off-peak window so it can discharge across the following day. The tariff structure that suits an EV owner charging twice a week isn't necessarily the one that suits a battery-only household cycling daily — see our guide on /tariffs/economy-7 for how the original version of this idea worked, long before EVs existed.

Do you need an EV to use these tariffs?

This is the single most common question we get, and the honest answer is: it depends on the tariff. Some tariffs — most notably Octopus Intelligent Go — are built around vehicle-to-grid style smart charging and require a compatible EV and, in many cases, a compatible smart charger to be registered on the account. Without the EV, you typically can't join, or you join but lose access to the cheapest rate.

Others are open to any household with a smart meter, EV or not. Octopus Go, OVO Charge Anytime, EDF GoElectric, Scottish Power EV Saver and the British Gas EV tariff all use a fixed overnight window that isn't gated behind vehicle ownership — the 'EV' branding is marketing, not an eligibility requirement, on most of these. That's the detail battery-only households need to check before ruling a tariff out.

Always confirm this directly with the supplier before switching, because eligibility rules and marketing names shift over time and we're describing the general shape of the market, not a live eligibility check for any specific supplier.

Fixed-window vs dynamic smart tariffs

A fixed-window tariff — the traditional Economy 7-style structure — publishes a set off-peak period, commonly overnight, and applies it consistently every day regardless of wholesale prices. It's predictable, simple to plan around, and works well with a battery on a timer or simple schedule, because you always know when to charge.

A dynamic or Agile-style tariff moves its cheap and expensive periods around based on wholesale electricity prices, sometimes updated daily or half-hourly. These can produce a lower average rate over time, but they require either manual attention or a smart control system (an EV charger, or a battery inverter with tariff integration) to actually capture the cheap periods automatically. For most battery-only households without that automation, a predictable fixed window is easier to get real value from day one, while a dynamic tariff rewards more active management.

The comparison table

The table below sets out the main tariff families by structure rather than by live pricing. Off-peak rate bands are illustrative examples only, labelled as such, and will not match what any supplier is currently charging — check the supplier's own tariff page for that.

How to pick one: a quick checklist

Start with whether you own or plan to own an EV. If not, cross off any tariff that requires one and focus on the fixed-window options open to any smart meter household.

Next, check the off-peak window length against how you intend to use it. A battery sized to cover a typical day's usage generally wants at least four to five hours of off-peak charging time to fill from empty, so a very short window may leave it topped up but not full.

Then look at the standing charge and the day-rate, not just the off-peak rate. A brilliant overnight rate can be offset by a higher standing charge or a steep daytime rate if your battery can't quite cover the whole day. Finally, check exit terms and whether the tariff is fixed for a set term or variable, since that affects how easily you can move again if a better deal appears.

Our /calculator can help you model how much of your daily usage a given battery size and off-peak window combination would realistically cover, which is a more useful exercise than comparing headline rates alone.

The battery angle: turning a short window into a full day

This is really the crux of why these tariffs matter beyond EV owners. A home battery charged fully during a cheap overnight window can then discharge across the following day, covering cooking, heating pumps, appliances and general household load at the off-peak rate rather than the day rate. In effect, a five-hour cheap window becomes a proxy for a 24-hour cheap tariff, provided the battery is sized appropriately for your daily consumption.

This is precisely why battery-only households — with no EV at all — have a genuine reason to care about tariffs that were originally marketed at EV owners. The vehicle in the marketing name is incidental; the mechanism (cheap overnight electricity, storable for later) is what a battery is built to exploit. See /guides/best-home-battery-uk for how battery sizing interacts with tariff choice in more detail.

It's worth noting that combining a fixed off-peak window with a battery is generally simpler to plan around than trying to chase a dynamic tariff without automation, because you can schedule the battery to charge in the same hours every night rather than needing it to react to a price signal it may not even receive.

Switching gotchas to check before you move

Exit fees: some fixed-term EV and overnight tariffs charge an early exit fee if you leave before the contract ends, though many modern tariffs are now exit-fee-free — check the specific terms rather than assuming either way.

Standing charges: off-peak tariffs sometimes carry a slightly higher daily standing charge than a plain variable tariff, to offset the discounted off-peak rate. Factor this into any before-and-after comparison rather than looking at the off-peak rate in isolation.

Minimum tenure and smart meter requirements: almost all of these tariffs require a working smart meter capable of half-hourly readings, and some require a specific meter type or firmware version. If your smart meter isn't currently sending readings, sort that with your supplier before applying, as it can hold up or block a switch. For background on how these tariff structures compare with mainstream time-of-use options, see /tariffs and /tariffs/octopus-tariffs-explained.

A note on tariff-switching help

We're evaluating tariff-switch partners — this section will link to one once we've assessed a comparison service we're comfortable recommending. In the meantime, we'd suggest checking rates and eligibility directly with each supplier rather than relying on third-party comparison tools that may not reflect the very latest terms.