Energy supplier switching figures from last month reveal the uncertainty in the energy market is pushing people towards established retail brands as large legacy suppliers saw their most positive month in eight years.

Of the 465,000 Changes of Supplier (CoS) completed in September 2021, three quarters of the switches were between large suppliers and to large suppliers from other suppliers.

  • Large to Large CoS reached 246,000 – 26 percent more than September 2020 and 53 percent of September 2021’s total switches completed,
  • Large to Other CoS reached 79,000 – 55 percent less than September 2020 and 17 percent of September 2021’s total switches completed,
  • Other to Large CoS landed at 100,000 – 46 percent more than September 2020 and 22 percent of September 2021’s total switches completed, and
  • Other to Other CoS hit 40,000 – 45 percent less than September 2020 and nine percent of September 2021’s total switches completed.

However, the month’s switching total is seven percent down on September last year, and the lowest September total since 2016. The majority of the switches completed in September were started in August when the price cap increase was announced and before the widely reported market disruption began, however this did not result in a boost in switches being completed.

There have been 4.3 million CoS completed so far this year, just three percent less than the same period last year.

There were 723,000 switches started in September 2021 – four percent less year-on-year despite being a large improvement on August 2021 and the month that tends to have the most switches started before the decline leading up to Christmas.

Due to ongoing challenges in the retail energy market following wholesale gas price rises, forecasting the number of CoS for the rest of the year is difficult. Price comparison websites have limited their energy comparison services and it is unlikely customers wanting to switch will be able to find a fixed deal that is not more expensive than the standard variable tariff price cap of £1,277.



ElectraLink and its staff are deeply saddened to learn that suppliers have recently exited the market, leaving customers without their preferred supplier and many of our industry colleagues now needing the next step in their careers. We trust the well-established Supplier of Last Resort (SoLR) process will ensure all end users have their supply continued. You can find out how we support this market process here.

The above figures relate to electricity CoS in Great Britain only.

We do not include CoS from SoLR processes or trade sales in our monthly CoS reporting. We account for only voluntary switches, or instances where the customer made an active decision and took action to change supplier.

CoS started refers to the number of valid switches started, also known as CoS raised.

All data is provided from the EMDH by ElectraLink’s Energy Market Insights team.

ElectraLink has been granted the governance protections to hold, transfer and analyse CoS and other data.