The move follows the Centrica-owned company's announcement last week that it has lost nearly 500,000 customers since January and that its prices are likely to increase by 15% because of ongoing gas shortages and the rise in wholesale prices.
The residential energy and home services divisions will have their own management teams.
British Gas managing director Mark Clare, who had been in charge of all operations, will work solely on the residential energy business.
Chris Weston, who was in charge of business customers, will run its home services division, which includes its servicing, installation and Dyno businesses.
Nick Smith, director of marketing, will continue to report to Clare, overseeing overall strategy and residential energy marketing. However, a spokesman confirmed that the company is looking for a marketing director for the home services division.
The new marketer will report to Weston, not Smith. The spokesman claimed the marketer would 'support' Smith in his role, but would run their own department.