So Energy So EV

Tariff availability, rates and terms were checked on 22 July 2026. They are a dated snapshot, so confirm the address-specific quote before acting.

So EV is an overnight off-peak electricity tariff from So Energy for homes that charge an EV at home. During the off-peak window, midnight to 5am, every unit of electricity the property uses is billed at the cheap rate, not only what the car draws. The current off-peak rate on So Energy’s tariff page is 7.5p per kWh. The tariff works with any EV and any home charger, needs a smart meter set to half-hourly readings, and So Energy backs the supply as 100% renewable.

Off-peak rate, peak rate and standing charge

So Energy’s page quotes 7.5p per kWh for the midnight-to-5am window. That rate has not held steady since the tariff launched. So EV started in July 2025 at 6.5p per kWh. By October 2025 So Energy’s own time-of-use article quoted 8.8p. The rate in mid-2026 is 7.5p. Comparison sites still carry a mix of these older figures, so the So Energy page is the only reliable place to read the current off-peak rate before you sign up.

So Energy does not display the daytime rate or the standing charge on the tariff page without a postcode, and it describes the daytime rate as its standard fixed-rate EV tariff rate. Third-party data from Best Chargers puts the peak rate at 27.82p per kWh and the standing charge at around 28p per day. That standing charge is low next to rival EV tariffs; Best Chargers lists Octopus at around 53p per day and E.ON Next at around 50p. Peak rates and standing charges vary by region across the UK market, so the figures for a specific address come from a So Energy quote.

Because the cheap rate is a whole-home rate, any load timed into the overnight window benefits, not only the car. A home battery charging from the grid, an immersion heater or storage heaters set to run between midnight and 5am all draw at the off-peak price.

What So EV can save

How much the tariff saves depends on how much of the home’s electricity moves into the five-hour window. So Energy’s own figures, based on a Tesla Model Y at 4.5 miles per kWh, put charging at 1.7p per mile and about 600 miles for under £10. It claims a 91% saving against the roughly 79p per kWh average public rapid-charging rate, and a 68% saving against its own So Flex standard variable tariff at 23.4p per kWh. Best Chargers estimated a full charge of a 60kWh battery at £3.90 on So EV against £14.99 at a standard rate, an £11.09 saving per charge, and put the annual saving at around £528 for 10,000 miles a year at 3.5 miles per kWh.

These figures assume a driver who charges overnight. The peak rate on a time-of-use tariff sits above a flat rate, so a household with high daytime use and modest mileage gains less, or can lose out, if too little of its electricity shifts into the cheap window.

Who can take the tariff

A household needs three things to take So EV: an EV, a home EV charger and a smart meter that can send half-hourly readings. The vehicle must be UK-registered and listed by the DVLA (Driver and Vehicle Licensing Agency) as fully electric or plug-in hybrid. So Energy confirms the car is a UK-registered EV as part of sign-up. The charger has to be a home charger the household uses to charge the car; charging only at public chargepoints does not qualify. If the property has no smart meter, So Energy installs one free. The meter has to be set to half-hourly readings, because that half-hourly data is what tells So Energy which usage falls inside the off-peak window.

So EV puts no restriction on the make of charger or the make of car. A household with more than one EV charges all of them on the same off-peak rate.

How to switch to So EV

New customers cannot join So EV directly. So Energy first puts them on So Flex, its standard variable tariff, and moves them to So EV once the smart meter is confirmed sending half-hourly reads, about five days after the supply transfer completes. Existing So Energy customers can switch from their fixed tariff to So EV at any time, a change that takes up to five days. To receive the invitation to move onto So EV you have to opt in to marketing communications during sign-up, the “I’d like to hear about rewards and receive updates” option.

Contract length and exit fees

The current product page describes So EV as a 12-month tariff. Existing So Energy customers can move from another So Energy fixed tariff to So EV without an early exit fee. Any fee for leaving So Energy during the term must be read from the quote and tariff information label supplied for that particular offer; the general terms are not a substitute for the contract-specific figure.

Tree and place names for the same tariff

Comparison sites sometimes list the tariff under names like So Larch EV or So Hampstead EV. So Energy uses tree and place names as internal codes for tariff versions and lists dozens of them. The consumer-facing name is So EV, and the tree- or place-named entries are the same tariff at a given version.

How So EV compares with other overnight EV tariffs

So EV’s main strengths are universal car and charger compatibility and a cheap band that covers the whole home. Its five-hour window is shorter than some alternatives, and there is no managed dispatch: the household sets the timer on the car or charger. A fair comparison must include the postcode-specific daytime rate, standing charge and exit terms, not only the 7.5p headline rate. It should also account for whether other loads or a home battery can use the cheap window.

The 100% renewable claim

So Energy describes the So EV supply as 100% renewable, backed by Renewable Energy Guarantees of Origin (REGO) certificates and power purchase agreements. So Energy’s overall electricity fuel mix is 53.3% renewables. The 100% figure reflects the certificate and purchase-agreement backing behind the tariff rather than the physical generation mix supplying the company as a whole.

Charger installation through So Energy

So Energy also sells and installs home chargers for customers who do not yet have one, with a VCHRGD Seven Pro from £929 or a Myenergi Zappi GLO from £999. A home charger is a condition of the tariff, so this is one route to meeting it, though any existing home charger of any make also qualifies.

Related entries

• So Energy supplier profile (the supplier behind the tariff and its wider range)
• Octopus Go and Intelligent Go (the smart-dispatch overnight tariff often compared against it)
• EDF GoElectric (another supplier’s overnight EV tariff)
• E.ON Next Drive (the seven-hour overnight EV tariff in the comparison)
• British Gas EV tariff (another whole-home overnight EV tariff)
• EV tariff charge windows (fitting a charge into the five-hour off-peak period)
• Smart meter SMETS2 capability (the smart meter the tariff requires)
• Half-hourly settlement data (the half-hourly readings that drive the two rates)
• Supplier exit and switching for TOU tariffs (exit fees and moving between time-of-use tariffs)