MediaCom has held the account since 2003, adding strategic buying and the Boots Healthcare International business in 2006.
The review, called in July, followed an internal restructure of Boots' marketing and trading teams that bought the two divisions together under Elizabeth Fagan, marketing director, with new directors for loyalty and customer relationship management, customer communications and in-store marketing.
Boots spent £49m on above-the-line advertising in the year ending September 2008, according to figures from Nielsen Media.
MediaCom is understood to be preparing to pitch for the £80m Tesco media planning and buying account. Tesco's media business is currently handled by Initiative, but sources suggest the agency has been put on notice by the client.