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Business Energy Contract Renewal: The Complete UK Guide

When to start your business energy renewal, how notice periods work, and the mistakes that quietly cost UK firms thousands each year.

28 July 2026 7 min read

Start six months before your end date

Business energy is bought forward. Suppliers price your contract against wholesale positions they hold months ahead, which is why the same meter can be quoted three very different prices in the same week. Starting your renewal six months out gives you a window to watch the market rather than accepting whatever lands on the day your contract lapses.

Most suppliers will let you agree renewal terms up to twelve months ahead of the start date. That does not mean you should sign the first offer twelve months out — it means you have the option to lock a good price when you see one.

Understand the notice period trap

Many business contracts contain a termination window. Miss it and the supplier can refuse a switch, leaving you on a deemed or out-of-contract rate that is typically 40-80% higher than a negotiated tariff.

  • Check the contract end date and the last day to serve notice — they are rarely the same
  • Serve written termination even if you intend to stay with the supplier
  • Keep proof of delivery; disputes almost always come down to evidence

Compare like for like

A headline unit rate means nothing without the standing charge, the contract length, and whether pass-through costs are fixed or floating. Two quotes at 24p per kWh can differ by hundreds of pounds a year once daily charges are included. Ask for annual cost projections based on your actual consumption, not a generic profile.

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