All Energy Suppliers

There are over 20 active domestic energy suppliers in the UK, offering hundreds of tariffs. Finding the best deal used to mean calling each one individually or using a comparison that only showed you a fraction of the market. Switcheroo shows you every available tariff from every active supplier, ranked by annual cost for your specific postcode and usage.

Ofgem’s price cap for Q2 2025 is set at £1,849 a year for a typical dual fuel household, still well above pre 2022 levels.

Whether you’re after the cheapest fixed deal, the greenest tariff, or the best smart meter plan, this page gives you an overview of every major UK supplier, with links to in depth reviews and comparisons for each.

Major UK Energy Suppliers Compared

How to Choose the Right Energy Supplier

• Compare on total annual cost, not just unit rate. Standing charges matter too.
• Check your contract end date. If you’re mid fixed deal, calculate exit fees before switching.
• Consider green credentials, fuel mix disclosures show where electricity actually comes from.
• Think about extras, HomeCare cover, smart tariffs, or EV charging rates may add value.
• Read recent customer reviews, Trustpilot and Citizens Advice rankings reflect service reality.
• Check your meter type, prepayment, smart.

Energy Suppliers for Specific Needs

Best for Customer Service

Octopus Energy consistently tops customer satisfaction rankings, Which? Recommended Provider for multiple consecutive years, 4.7★ on Trustpilot. See our Octopus Energy review.

Best for Green Energy

Octopus and ScottishPower both generate their own renewable electricity. EDF offers the UK’s largest low carbon generation fleet. For the full picture, see our Compare Green Energy page.

Best for Smart Tariffs and EV Owners

Octopus Agile and Intelligent Go are the market leaders. EDF’s GoElectric and OVO’s Drive are strong alternatives. See our EV Chargers guide for the full EV tariff comparison.

Best for Broadband + Energy Bundle

Utility Warehouse bundles energy with broadband and mobile. Compare the bundle total against sourcing separately on Switcheroo. For standalone broadband, see our Compare Broadband page.

Best for Boiler Cover

British Gas HomeCare is the most comprehensive boiler and home cover product from any energy supplier. For a full comparison of boiler cover options, see our Boiler Cover page.

Our advice: don’t just pick the cheapest headline rate. Check the exit fees, customer service scores, and whether the supplier handles smart meters before you commit.

• Review your choice every 12 months, the cheapest supplier this year may not be next year
• If you’re on a smart meter, prioritise suppliers who offer time of use tariffs, they can unlock significant savings
• Look at the Citizens Advice star rating for an independent view on complaint handling and switching performance
• Check whether the supplier is FCA regulated or Ofgem licensed, all retail energy suppliers should be Ofgem licensed
• Start with price, but weight customer service ratings equally, a cheap supplier with poor billing accuracy causes real headaches

How to Choose the Right Energy Supplier

Price is the most visible comparison point, but it’s not the only one that matters. Customer service quality varies significantly between suppliers, Citizens Advice publishes a quarterly star rating that covers complaint volumes, billing accuracy, and switching performance. Some households prioritise green credentials; others value the simplicity of a bundle with broadband or phone. Smart tariff availability matters if you have an EV or want to shift usage to cheaper overnight windows. Exit fee policies differ too, Ofgem caps these at £30 per fuel, but some suppliers are quicker to waive them than others. The Warm Home Discount (£150 per year for qualifying households) is available through most large suppliers but not all smaller ones, worth checking if you might be eligible.

What to Look for Beyond the Price

The UK has around 25-30 active retail energy suppliers, ranging from the former big six (British Gas, EDF, E.ON, OVO/SSE, Octopus, and Scottish Power) to smaller challengers and specialists. Since the 2021-22 energy crisis, over 30 suppliers exited the market, some failed, others were absorbed. The market is now more concentrated than it was in 2019, with Octopus Energy growing substantially through acquiring customers from failed suppliers. All licensed suppliers are regulated by Ofgem, which sets standards on billing, customer service, debt recovery, and the price cap. Switching between licensed suppliers is straightforward, Ofgem rules require transfers to complete within 17 working days, and suppliers are obligated to inform you about your right to switch.

Big Six vs Independent Suppliers: Which Is Better?

The UK energy market includes the ‘Big Six’ (British Gas, EDF, E.ON, NPOWER, Scottish Power, SSE) and dozens of independent suppliers (Octopus, Bulb, Utility Warehouse, OVO, etc.). Big Six suppliers are established with large generation assets, extensive customer bases, and strong capital reserves. They’re stable and unlikely to collapse, but they’re rarely the cheapest; economies of scale don’t translate to lower prices because they’ve grown through market inertia rather than competitive innovation. Independent suppliers emerged with newer technology (cloud based systems), leaner operations, and aggressive pricing. Octopus Energy exemplifies this: founded 2015, they’re now the second largest UK supplier by customer count, competing primarily on price and customer experience. Smaller independents are riskier (they collapse more often) but often significantly cheaper. The question ‘Big Six vs independents’ boils down to risk tolerance versus savings. If you prioritize stability, Big Six is safer. If you want the cheapest rates and don’t mind switching if a supplier fails, independents offer better value. The 2021–2023 crisis proved the safety net works; collapsed suppliers’ customers transferred to new suppliers without losing money (though they lost guarantees). Most people should shop on price; supplier size matters less than Ofgem’s protections.