The agency landed the account after a pitch against the incumbent, Libertine, Rainey Kelly Campbell Roalfe/Y&R, Publicis London and Iris.
Mother will push the Butlins brand through TV and print, while providing strategic direction in terms of its online, in-resort and brochure communications.
Butlins, which is owned by Bourne Leisure, celebrates its 75th anniversary next year and called the pitch in a bid to ensure that its creative message "reflects the uplifting spirit of the resort experience and the award-winning attitude of the team".
Butlins is currently running a television ad, by Libertine, called "circles", which is accompanied by a version of the 80s Dead or Alive song You Spin Me Round (Like A Record).
Jackie Martin, the sales and marketing director for Butlins, said: "Now is the time to embrace the creative and dynamic proposals which Mother presented to us, which we believe will move Butlins even further ahead in the market."
Media planning and buying for Butlins, which is held by Zed Media, is unaffected by the creative appointment.