Below we have listed every current UK energy supplier in the domestic market.
We have also listed how many customers or accounts each of these suppliers has as of August 2025.
How many accounts/customers does each UK energy supplier have?
Most of the available information on the number of customers energy suppliers have is based on electricity and gas accounts rather than households. For example, if you are a gas and electricity customer with the same supplier, you would have two accounts.
In the table below, we have used the data from Ofgem, where it is available. This is the latest available data as of 1st August 2025.
Smaller suppliers don’t have to give this data to Ofgem, so we have used other data where possible for those suppliers. This won’t be as accurate because sometimes they use the same metric as above, and other times they use households instead. The numbers are generally rounded up or down and are likely less up-to-date.
You can see our full list of UK suppliers and their accounts/customer numbers below:
| Supplier Name | Electricity Accounts | Gas Accounts | Total |
|---|---|---|---|
| 100Green (7) | 50,000 | ||
| British Gas | 5,031,627 | 5,690,464 | 10,722,091 |
| Co-Operative Energy (1) | 300,000 | ||
| E (Gas and Electricity) (2) | 300,000 | ||
| E. ON Next | 4,272,131 | 2,933,268 | 7,205,399 |
| Ecotricity (3) | 200,000 | ||
| EDF Energy | 2,684,464 | 1,910,290 | 4,594,754 |
| Fuse Energy (8) | 50,000 | ||
| Good Energy (4) | 200,000 | ||
| Home Energy | Unknown | ||
| Octopus Energy | 6,701,853 | 5,925,232 | 12,627,085 |
| Outfox Energy (5) | 100,000 | ||
| Ovo Energy | 3,018,729 | 2,136,874 | 5,155,603 |
| Sainsbury’s Energy | Unknown | ||
| Scottish Power | 1,895,024 | 1,450,581 | 3,345,605 |
| So Energy | 285,836 | 251,333 | 537,169 |
| Tulo Energy | Unknown | ||
| Utility Warehouse | 487,781 | 747,069 | 1,234,850 |
| Utilita Energy (6) | 775,000 | 648,000 | 184,017 |
Who are the biggest suppliers in the UK?
According to Ofgem’s State of the Energy Market Report, six suppliers now account for around 91 % of the domestic market. The current composition is:
- Octopus Energy
- British Gas (Centrica)
- E.ON Next
- OVO Energy
- EDF Energy
- ScottishPower
Which suppliers have gone bust?
In September 2021, the ‘energy supplier crisis’ began, with many energy suppliers going bust.
Our top rated supplier Octopus Energy is currently offering £50 credit to any new customer that uses our referral link. Click below to see why we rate them so highly and get your £50.
