British Gas is calling a direct marketing review. The business is currently split between WWAV Rapp Collins and EHS Brann.
The energy company says it needs to reconsider arrangements to ensure it meets "long-term business and marketing objectives". Both agencies have worked with the brand for more than a decade.
Brand marketing director Amanda Mackenzie says: "As a matter of due diligence it is time we paused for breath to see if we can work smarter."
Mackenzie, former BT marketing director, joined British Gas in September last year to replace Nick Smith.
She joined after quitting her role as Hewlettt-Packard vice president of marketing, EMEA in August last year.
The pitch will begin in January with a decision due by May.
The Centrica-owned energy provider handed its £30m creative account to Clemmow Hornby Inge in May 2003 following a four-way pitch. The appointment put an end to its 12-year relationship with DDB London. Media planning and buying is handled by Carat, which according to British Gas will not be affected by the review.