49 Day Rule Calculator
Contents
If you are on a domestic fixed rate energy tariff with exit fees, Ofgem’s switching window protects you from the termination fee. It opens when your supplier provides its renewal statement or 49 days before the fixed term ends, whichever is earlier. The calculator shows the 49-days-before date; check your statement because your protected window may have opened sooner.
Rule basis: Ofgem’s domestic gas and electricity supply licence conditions 24.8(b) and 24.17. See Ofgem’s current consolidated licence conditions.
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Month-end tariff dates
| Your tariff end date | The 49-days-before date is |
|---|---|
| 31 January | 13 December |
| 28 February (non-leap year) | 10 January |
| 29 February (leap year) | 11 January |
| 31 March (non-leap year) | 10 February |
| 31 March (leap year) | 11 February |
| 30 April | 12 March |
| 31 May | 12 April |
| 30 June | 12 May |
| 31 July | 12 June |
| 31 August | 13 July |
| 30 September | 12 August |
| 31 October | 12 September |
| 30 November | 12 October |
| 31 December | 12 November |
Enter a valid tariff end date.
Frequently asked questions
What is the 49 day rule for energy tariffs?
Under Ofgem’s domestic supply licence, you can switch supplier without a termination fee during the switching window. That window begins when your supplier provides its renewal statement or 49 days before the fixed term ends, whichever is earlier. This calculator shows the 49-days-before date; your statement may give you an earlier date.
Do I have to pay exit fees to leave my energy tariff?
You can switch supplier without a termination fee once your switching window has opened. It opens when your supplier provides its renewal statement or 49 days before the fixed term ends, whichever is earlier. Before then, your supplier may charge an exit fee — but many fixed tariffs have none. Across the fixed tariffs on the market in August 2026, roughly a third carried no exit fee at all, and where one applied it ran from £25 to £100 per fuel, with £75 the most common. On a dual fuel tariff you would pay it on each fuel, so check your own tariff terms rather than assuming a figure.
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Written by
Rob Gibbs
Hi, I'm Rob, and I run Energy-Review.co.uk. I initially started this project in 2018 when I was looking to switch energy suppliers and found there wasn't a website that provided simple, data-backed reviews on all the suppliers available. Since then, I have spent a lot of time (too much, some may say!) looking at all publicly available data about each supplier and writing reviews using this information. These reviews are updated as regularly as possible, and any data is backed up by a source where necessary. I have also started writing guides on various energy-related topics, which hopefully you will find useful. If you find any issues, please use our contact form to let us know.