The account will be handled by WCRS's below-the-line arm Personal, which was launched in July 2004.
The move will be a blow for Tequila, the below-the-line TBWA\ sister network, which has worked with Abbey for a number of years.
The move of the direct response account follows the appointment of WCRS to Abbey's 拢22m ad account in March.
The ad account had previously been held by TBWA\London, which has suffered a string of account losses of late, most recently losing FCUK to Trevor Beattie's start-up and the News Group Newspaper's account.
Jeremy Davies, Abbey's director of brand and communications, said: "This is a commercial decision and in no way reflects the quality of work produced by Tequila, which Abbey has been very pleased with.
"The relationship between the two companies remains strong and Tequila will continue to work on Abbey's direct marketing activity."
In April, Abbey moved its 拢7m digital account out of Tequila into Grand Union.
Abbey has recently launched a major new integrated advertising campaign with TV, posters, press and radio to run until the end of June.
The new endline used across all ads is "Abbey. More ideas for your money" and is the first time that the new logo, created following the takeover of the company by Grupo Santander, has been used on ad material.
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