2021 ended with a new record low number of switches in December as high wholesale energy prices continue to push suppliers out of the market and customers are transferred to suppliers of last resort (SoLRs).

A combination of SoLR transfers and voluntary switches to more well-known brands has increased the former Big Six’s market share for the first time in a decade. At the end of August 2021, large legacy brands held accounts with 56 percent of customers in Britain. At the end of December 2021, their market share equalled 59 percent of customers.

As of 31 December, large suppliers hold 25 percent of the market share, medium suppliers 11 percent and small suppliers four percent.

As of writing, 27 small and medium suppliers have exited the market since summer 2021. Analysts across the media and energy market have suggested more supplier exits are inevitable before wholesale energy prices stabilise.

Despite the large legacy brands taking on many new customers, supplier changes in general have continued to suffer due to the energy crisis and the usual dip in customers’ appetites to change supplier during the festive period. December 2021 marked a new low for monthly changes of supplier (CoS) as 112,000 switches completed – lower than the record low set the month before and 77 percent less than December 2020.

CoS started in December also plunged to a record low. 141,000 CoS were initiated – at least 74 percent fewer than December 2020 and over 20,000 fewer than the previous record low set in November last year.

The number of CoS completing in January will likely be less than December’s attempts. Our analysts believe CoS completed in January could fall below 100,000.

Turning to switching types, the same distribution of switches between certain types of supplier remained the same in December as in the rest of the year, although in much more limiting conditions.

  • Large to Large switches reached 64,000 – 73 percent less than December 2020 and 57 percent of December 2021’s total switches completed,
  • Large to Other switches reached 19,000 – 87 percent less than December 2020 and 18 percent of December 2021’s total switches completed,
  • Other to Large switches landed at 21,000 – 70 percent less than December 2020 and 17 percent of December 2021’s total switches completed,
  • And Other to Other switches hit 9,000 – 81 percent less than December 2020 and 8 percent of December 2021’s total switches completed.

2021 switching roundup

Overall, there were 4.984mn successful supplier switches in 2021 – 18 percent less than 2020 and over a fifth less than 2019; this has effectively put customer switching back by five years.

However, with all the switching activity due to supplier mergers and SoLRs, the CoS process was used over 11.2mn times; a 37 percent increase on 2020. That means nearly a third of all MPANs went through the process last year, but less than half of those were at the request of a customer.

When analysing voluntary customer switching on a regional basis, Yorkshire saw the highest level of engagement last year, with almost 16 percent of MPANs going through a customer-initiated supplier change. The lowest was North Scotland with over 12 percent of MPANs undergoing voluntary switches.

In 2020, the most active MPAN changed supplier 17 times. In 2021, the record number was only 14 switches, but it was the same MPAN that switched 17 times in 2020. 93 percent of MPANs that switched did so once only – a remarkably stable statistic. The highest proportion was 94 percent in 2014, the lowest 92 percent in 2019.

In 2021, 1.1m MPANs switched supplier voluntarily for the first time. That takes the total number of MPANs that have switched since April 2012 to 19.75mn, meaning roughly 63 percent of customers have chosen to change supplier in the last 10 years. It also means there are around 11mn MPANs that, unless they have been sold or merged, are still with the same supplier as they were in 2012. The vast majority of those will be on legacy suppliers, or SSE under Ovo’s ownership.

For more information on CoS figures, or to find out how your organisation can access the CoS data we hold and provide for the energy market, contact [email protected].



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 by ElectraLink’s Energy Market Insights (EMI) from the EMDH.

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