Dual Fuel vs Separate Energy Suppliers

    Most UK households take gas and electricity from the same supplier ("dual fuel"). It's simpler — but it's not always cheaper.

    When dual fuel wins

    • Suppliers offer dual-fuel discounts (£15–£30/yr).
    • One bill, one direct debit, one customer service line.
    • Easier to switch as a single transaction.

    When splitting wins

    • The cheapest gas tariff and cheapest electricity tariff are at different suppliers — and the gap is more than £30/yr.
    • You want a 100% renewable electricity supplier but cheap gas.
    • You're on Economy 7 and need a specialist time-of-use deal.

    Bottom line: always compare the true annual cost of "dual" against "best-of-both" before assuming dual fuel is cheapest. And whichever route you pick, make sure your meter is reporting correctly — see common smart meter problems and how to fix them so both fuels are billed on real usage.

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    Switching and supplier performance

    This page sits inside our guide to comparing UK energy suppliers, which brings together supplier performance scores, tariff types and the switching process.

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    Compare Energy Suppliers

    Independent PowerGuardian scores out of 100 for relevant suppliers, as at 21 September 2026.

    Octopus Energy

    92/100

    Octopus continues to lead the UK market on customer service and complaint handling, backed by genuinely competitive smart tariffs and strong financial backing. The clear front-runner on our intelligence dashboard.

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    EDF Energy

    73/100

    EDF is a steady, financially robust supplier with mid-table service and fair fixed-tariff renewals. Few surprises in either direction.

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    British Gas

    55/100

    The UK's largest supplier remains financially rock-solid but service and complaint metrics continue to lag the market, with smart-meter billing delays a recurring theme.

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