The Prudential-owned internet bank has tasked the agency with overhauling its cashback scheme to revive customer interest in its banking and credit-card business.
The scheme currently rewards cardholders with discounts of between 5% and 20% when they make purchases from affiliated brand, which include Virgin Wines, Currys, lastminute. com and Selfridges.
The first phase of pro-motional activity will be a Christmas-themed drive targeting 1m cardholders, intended to broaden awareness of its partnerships and the cashback programme.
This will be followed by a regular monthly email informing customers about the potential benefits of their Egg Visa Card or Egg Money account.
Neither Egg's direct agency, Claydon Heeley Jones Mason, nor its digital agency, Agency Republic, will be affected by the appointment of WDMP.
Egg unveiled an £8m TV campaign promoting its Egg Money hybrid credit/debit account earlier this month. The work continues the 'guinea pig' creative theme used in its print and radio ads (Marketing, 2 November). The activity is the bank's biggest since the Egg card's debut six years ago.
Egg has a 3.6% share of the credit-card market, according to Mintel.
The market leader is Barclaycard, with a 14.2% share.
Last month, Prudential confirmed it is no longer looking to offload the Egg business. It is now exploring ways of getting the businesses to work together.