This is a record high since 2013 when Energy UK started publishing data, and is an increase of 26% on 2015.
This continues the trend of increasing overall switching figures for the past two years. The average number of monthly switches was over 400,000 in 2016. In December, the number of switches reached 449,921, up by a third (33%) compared to December 2015.
One in five (22%t) of those electricity switches in December were to a smaller supplier.
The introduction of the Energy Switch Guarantee last year also helped make switching easier and provided greater confidence for customers when switching supplier. New research for the Guarantee also reveals nine in ten (89 percent) people were satisfied with the overall switching process.
Lawrence Slade, Chief Executive, Energy UK, said: ““It is fantastic that switching levels are continuing to soar – with almost five million households changing supplier last year.
“Across the industry, energy companies are doing more to engage with all of their customers, making it easier for people to be on the right tariff whether that’s with their current supplier or by switching to one of the 40 plus suppliers active in the market.”
Juliet Davenport, chief executive of independent renewable supplier Good Energy, commented: “For far too long the Big Six have taken loyal customers for granted. Smaller suppliers are increasingly taking customers away from old-fashioned energy companies as consumers look for better service, fairer prices and greener energy.”