How rival EV tariffs actually bill your home in 2026

A lot of older EV tariff advice is already out of date because the market has split into different billing models. That matters just as much as the off-peak price itself.

In April 2026, Octopus Go still gave a simple cheap window from 00:30 to 05:30. Intelligent Octopus Go gave six whole-home off-peak hours from 23:30 to 05:30, plus smart charging at a lower published rate. E.ON Next Drive Smart, British Gas EV Power, OVO Charge Anytime and ScottishPower EV Optimise all structure EV charging differently. The unit rates change, so use this article for the billing model and check each supplier's current page for today's prices.

The practical question is not only which tariff is cheapest on paper. It is what gets the cheap rate, when, and how that saving actually reaches your bill.

1. The simple cheap-window model

This is the easiest version to understand. The tariff gives your whole home a cheaper unit rate during a fixed overnight block. Your car can use it, but so can the washing machine, immersion heater or home battery.

• Octopus Go: cheap whole-home electricity from 00:30 to 05:30.
• British Gas EV Power: an overnight cheap window, with the cheap rate available across the home, not only for the car. Check British Gas for the current unit rate and hours.
• ScottishPower EV Saver: a more traditional overnight time-of-use setup. Check ScottishPower for the current rate and hours.
• E.ON Next Drive: a non-smart sister tariff to Drive Smart, aimed at drivers who mainly want a longer overnight window.

This model suits households that like predictability. You know when the cheaper period starts, when it ends and what else in the house can benefit. It is often the best fit if you already charge overnight and do not want your supplier managing the car actively.

2. The whole-home smart-spillover model

This is where the tariff starts to feel different from an old-fashioned off-peak meter. The supplier still gives you a guaranteed cheap period, but smart charging can also create extra cheap periods outside the usual overnight slot.

• Intelligent Octopus Go: your home gets six guaranteed off-peak hours every night, and when Octopus schedules smart charging outside that window, the rest of the home also gets the cheap rate during those scheduled periods.
• E.ON Next Drive Smart: your whole home gets a cheap overnight window, and E.ON says the same smart-charge rate can also apply across the home during app-scheduled daytime charging. Check E.ON for the current rate and hours.

This model can work well for people who want the supplier to do more of the work. It can also trip people up, because the cheap rate is no longer only about one fixed overnight block. You may see cheaper charging at odd times of day, but only when the smart schedule is actually active.

That is why drivers keep mixing up the car benefit and the household benefit. The tariff can be generous, but the rules are more conditional than on a simple overnight product.

3. The add-on or bill-credit model

This is the model that causes the most confusion in 2026. The headline rate may look competitive, but your home is not really on a classic EV tariff in the old sense.

• OVO Charge Anytime: your normal home tariff stays in place. The EV charging is handled as a smart-charging add-on, either through monthly plans with included home-charging allowances and public-charging vouchers, or through a pay-as-you-go smart-charging rate. Check OVO for the current rate and allowance figures.
• ScottishPower EV Optimise: you are billed first at your normal tariff rate, then the difference down to the advertised smart-charging rate is credited back later as a separate line on the bill. Check ScottishPower for the current credited rate.

This model is not necessarily worse. It can be useful if you want daytime charging flexibility or already like your main household tariff. The catch is that the home and the car are being treated differently. Your kettle, oven and heat pump do not automatically follow the EV rate. In some cases your EV savings arrive later as a credit instead of showing up instantly in the unit rate.

OVO is the clearest example of why old comparison pages can mislead people. It is no longer best described as a simple cheap overnight tariff. It is now closer to an EV charging plan that sits on top of your normal electricity deal.

4. What this means in real life

• If you want one cheap household window you can build routines around, the simple whole-home model is still the cleanest answer.
• If you want the supplier to schedule charging more actively, the smart-spillover model can be stronger, but only if you are happy with the app rules and compatibility limits.
• If you mostly care about EV charging itself and are relaxed about the rest of the house staying on a normal tariff, an add-on or bill-credit model may still work well.
• If you also have solar panels or a battery, the difference becomes even more important because some tariffs reward home-wide load shifting better than others.

This is also why the cheapest EV headline is not always the cheapest home energy outcome. A whole-home a simple overnight window can sometimes beat a clever-looking add-on if you also run appliances, charge a battery or heat water overnight.

5. A quick checklist before you switch

1. Check whether the cheap rate applies to the whole home, only to smart EV charging, or arrives later as a bill credit.
2. Check whether there is a guaranteed fixed overnight window, or whether most of the value depends on smart scheduling.
3. Look at what happens if you need an urgent or unscheduled charge.
4. Check compatibility carefully, especially if the tariff relies on a specific car, charger or app.
5. Think about the rest of the house, not just the car. A tariff that suits an EV on paper may be weaker for a home with solar, a battery, immersion heating or heavy overnight use.

Bottom line

The healthiest way to compare EV tariffs now is to stop asking only, "what is the cheap rate?" and start asking, "how does this tariff treat my whole house?" That one shift makes the market a lot easier to read.

If you want the simplest answer, start with tariffs that give the whole home a clear cheap window. If you are comfortable with smart scheduling, products like Intelligent Octopus Go and E.ON Next Drive Smart can be strong. If you are looking at OVO Charge Anytime or ScottishPower EV Optimise, check the bill mechanics carefully: you may be comparing an EV charging product, not a classic all-house EV tariff.