The St. Louis-based company made the appointment after a pitch that included incumbents Aegis Group-owned Carat and Vizeum, and Omnicom Group's PHD.
The consolidated account includes the Energizer battery and Wilkinson Sword brands.
Last year, Energizer spent over $130m (£65m) in measured media according to Nielsen Monitor-Plus.
The review began in the autumn and was kicked off to consolidate its media planning and buying into a single agency. It had previously split its business between PhD, which handled the batteries business, and Carat and Vizeum agencies, which handled the buying and planning on Schick respectively.
Jacqueline Burwitz, vice-president of investor relations for Energizer, said: "The consolidation of the batteries and blades media planning and buying in North America reflects our ongoing commitment to drive both effectiveness and efficiency wherever possible throughout our operations."