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UK domestic energy supplier

So Energy UK

Founded in 2015 and headquartered in Chiswick, London, So Energy supplies gas and electricity to UK households. Compare tariffs, customer service, complaints and ownership below.

Founded 2015 Approximately 300,000 households (2026, 10-year anniversary) Chiswick, London

Founded

2015

Years on the UK market

Customers

Approximately 300,000 households (2026, 10-year anniversary)

Households served

About

Who is So Energy?

Registered as So Energy Trading Limited, So Energy uses this legal name for Ofgem licence filings, contracts and any formal communications. The trading name customers see on bills is the shorter, more recognisable form.

The company is headquartered in Chiswick, London, where it runs its senior management, customer operations and regulatory liaison with Ofgem.

So Energy was established in 2015. A longer track record means more years operating under Ofgem rules and a wider history of customer feedback, billing systems and regulatory interactions.

So Energy is part of the ESB Group (Ireland) group, which provides shared governance, financial backing and a broader pool of expertise in trading, hedging and regulatory work.

The company is regulated by Ofgem, the UK's energy regulator, and its complaint handling falls under the Energy Ombudsman alternative dispute resolution scheme.

Fuel mix

So Energy electricity fuel mix

So Energy supplies 100% renewable electricity on every tariff except <strong>So Flex</strong>, with each kWh matched annually by a Renewable Energy Guarantee of Origin (REGO) certificate. Customers historically voted on the mix between wind, solar, hydro and biomass — the supplier publishes the resulting blend every quarter. Gas is not certified as green.

  • Renewable 100%

Current tariffs

So Energy tariffs: as of May 2026

The Ofgem Energy Price Cap fell to £1,641/year for a typical dual-fuel direct-debit household on 1 April 2026 (down £117 since January). The cap limits the unit rate and standing charge on So Energy's default So Flex variable tariff. So Green Tracker is guaranteed to sit £50/year below the cap (£25 per fuel) for a 12-month commitment, and resets every three months alongside the cap. The fixed range (So Hawthorne, Kings, Kielder, Larch) sits at or slightly above the cap — So Energy itself says wholesale prices are too high in 2026 to price fixed deals below cap. Rates below are cap-aligned approximations for the East England region; pull the live Tariff Information Label (TIL) from so.energy for the exact figures in your postcode.

So Energy domestic and business tariff unit rates as of May 2026
Tariff Type Unit rate

So Green Tracker

Variable tracker tariff guaranteed to stay £50/year below the Ofgem default-tariff price cap (£25 per fuel) at typical dual-fuel usage. Rates and standing charges reset every three...

Term: 12 months · no exit fee

Tracker 5.54 p / kWh

So Fixed 12 (Hawthorne / Kings / Kielder / Larch)

Fixed-rate range — So Energy issues the deals under four product names (Hawthorne, Kings, Kielder, Larch) depending on the launch window. Unit rate and standing charge are locked f...

Term: 12 months · exit fee £75/fuel

Fixed 6.46 p / kWh

So Fixed 24

Two-year version of the fixed range — same lock-in mechanics, longer horizon. Better priced than the 12-month deal in some launch windows when So Energy wants to grow the long-tenu...

Term: 24 months · exit fee £75/fuel

Fixed 6.62 p / kWh

So EV

Time-of-use tariff for EV drivers. Off-peak rate of 8.8p/kWh kicks in overnight between 12 a.m. and 5 a.m.; peak rate applies for the rest of the day. 100% renewable electricity. R...

Term: 12 months · exit fee £75/fuel

Smart EV 8.80 off-peak (12 a.m. - 5 a.m.) p / kWh

So Unique

Personalised time-of-use tariff. Uses 12 months of half-hourly smart-meter data to build a peak / off-peak / super off-peak rate schedule tailored to your individual usage curve. S...

Term: 12 months · exit fee £75/fuel

Smart ToU see TIL (personalised) p / kWh

So Flex

Default variable tariff and the only non-green tariff in the So Energy range. Unit rate and standing charge reset every three months at the Ofgem cap level. No exit fee, no minimum...

Term: No fixed term · no exit fee

Variable 6.46 p / kWh

Regulator

Who regulates So Energy?

Independent watchdog responsible for licences, price approvals and customer-protection rules.

Complaints escalation (ADR)
Energy Ombudsman

If So Energy does not resolve your complaint within eight weeks (or issues a deadlock letter sooner), you can refer it free of charge to the Energy Ombudsman. The Ombudsman's decision is binding on the supplier.

Companies House
09263295

Timeline

So Energy — key dates

A short timeline of the So Energy brand — founding, milestones, regulatory events.

  1. 2015

    So Energy is founded by school friends Charlie Davies and Simon Oscroft in London, joining the wave of challenger energy companies disrupting the Big Six.

  2. 2020

    So Energy ranks among the top-rated suppliers in Which? annual energy satisfaction surveys.

  3. 2021

    Irish utility ESB Group acquires a majority stake in So Energy in August, securing its future during the wholesale-price crisis.

  4. 2022

    So Energy merges retail operations with ESB Energy UK; combined customer base grows to about 250,000 households.

  5. 2024

    So Energy continues to offer 100% renewable electricity with a 12-month fixed tariff range and launches the So EV time-of-use tariff for electric-vehicle drivers.

  6. 2025

    So Energy marks its 10-year anniversary and trials a personalised smart ToU tariff (So Unique) against the default So Flex rate.

  7. 2026

    Customer base reaches approximately 300,000 households. April price cap reduction (£1,641 typical dual fuel) feeds through to all variable and tracker tariffs; So Green Tracker continues to sit £50/year below the cap.

Customer service

How to reach So Energy in 30 seconds

The lines you actually need on speed-dial. Every other line (Welsh, Relay UK, business switching, bereavement) is on the full contact page.

Online portal

My Account

Bills, meter readings, payments

Gas emergency (free, 24/7)

0800 111 999

National Gas Emergency line

Save up to £300 per year
Independent comparison

Is So Energy the cheapest option for your home?

UK households can save up to £300 per year by switching to a supplier whose tariffs fit their actual gas + electricity usage. Compare against suppliers regulated by Ofgem in under two minutes.

Common questions

So Energy — frequently asked questions

So Energy is regulated by Ofgem and operates under a standard domestic-supply licence. Whether it is the right supplier for your household depends on your unit rate, standing charge, customer-service rating and any add-on services (HomeCare, Warm Home Discount eligibility). Always quote your annual kWh consumption when comparing prices — the headline rate alone does not predict your bill.

Switching to So Energy takes about five working days under the new Faster Switching service, and your supply is never interrupted. Sign up online with your address, postcode and a recent meter reading. So Energy will arrange the transfer with your current supplier, including the final meter reading and the closing bill.

The UK grid is supplied by a mix of gas, nuclear, wind, solar, biomass and imports. So Energy declares its fuel mix annually under Ofgem rules — see the fuel-mix section above for the current figures. Some tariffs are sold as 'green' or '100% renewable', which means the supplier matches your annual consumption with renewable electricity certificates (REGOs) rather than physically delivering renewable electrons to your home.

Most UK fixed-term tariffs include an exit fee (typically £25-£75 per fuel) if you switch before the contract ends. You can switch without an exit fee in the last 49 days of your contract. Variable tariffs (including the default tariff capped by the Energy Price Cap) have no exit fees.

You can reach So Energy on 0330 111 5050, Mon-Fri, 9 a.m. to 5 p.m. (closed bank holidays). For a full breakdown of phone lines (emergency, prepayment, HomeCare, bereavement, Welsh, Relay UK), see the So Energy contact page.

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