Ofgem, the UK's energy regulator, publishes the current energy price cap per region. Note that it is only the current price cap. I couldn't find the complete historic data on their site. So I sent a quick email asking for it which they treated as a Freedom of Information request.
Please can you supply me with a complete list of all previous electricity price cap figures?
I have searched your website and can only find the current price-cap.
Specifically, I would like to know the per kWh price cap for electricity in the London region from its introduction until today.
If these are on your website, please point me in the right direction. If not, a CSV of the data would be appreciated.”
A month later, and without any fuss, they emailed me a comprehensive spreadsheet. In Excel format, but let's not quibble!
There are a few formatting oddities - not least that the caps are expressed with 13 decimal places of precision. Was the daily cap really 60.9345205479452p?
Similarly, the dates are expressed as 1 April 2022 to 30 September 2022 rather than programmatic date ranges. It's also inconsistent, with some saying 1 July to 30 September 2025.
Averages are hard-coded not calculated.
I've requested that they add these data to their website but, until they do, here's the original file they sent me.
I've used a bit of R to tidy them up, giving proper start date and end date columns, rounding to 2 decimal places, and saving as CSV. You can download the tidied version.
Copyright and Copyleft
As per their copyright page these data are © Ofgem, 2026 and are licensed under the Open Government Licence 3.0. This is compatible with CC BY and ODC-By.
Please treat my update as Creative Commons Attribution.
One thought on “Historic Energy Price Cap Data (FOI success!)”
Stuart Bonell
Thanks for this. Just been trying to compare our use of an Octopus Tracker tariff against the price cap alternative looking back.
I'd found https://www.electricityprices.org.uk/history-of-the-energy-price-cap/, but that's a national average rather than all regional data.
Astonishing, but not actually surprising (?), that the suppliers, Ofgem/anyone don't make this available. I also had to source my daily tariffs from Octopus which wasn't as easy as it should be either. They provide it on the PDF bills, but not as downloadable data....or at least that's what they told me.
They do actually provide a download option which shows daily cost and daily usage, so it's trivial to derive the tariff rate (and bizarre that they don't include in the data set anyway).
Well done again for getting hold of this.
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