Fixed vs Variable Energy Tariff

    Choosing between a fixed and variable tariff is the single biggest decision affecting your UK energy bill this year. Here's how they compare.

    Fixed tariff

    Unit rates and standing charges are locked in for 12–24 months.

    Pros

    • Price certainty
    • Often cheaper than the cap

    Cons

    • Exit fees (£75–£150/fuel)
    • Lose out if wholesale prices fall

    Variable tariff

    Rates move with the Ofgem cap, updated every 3 months.

    Pros

    • No exit fees
    • Benefit if prices fall

    Cons

    • Bills can rise with little notice
    • Usually capped, not cheapest

    Which should you pick?

    If a fixed deal is at least 5% below the current cap and you value certainty, fix. If the market is forecast to fall meaningfully and you can absorb short-term swings, stay variable.

    Should I switch right now?

    Frequently Asked Questions

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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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    Should I Switch Energy Supplier?

    Is switching worth it right now? A decision framework using the current cap and fixed-deal evidence.

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    Compare Energy Suppliers

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

    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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    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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    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.

    Compare Supplier

    Frequently Asked Questions

    Quick answers to the questions people ask most about this topic.

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    Standing Charges Report

    A deep dive into the daily fixed fees on every UK bill — regional differences, drivers and the case for reform.

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