The PepsiCo-owned operation has invited OMD UK to pitch against the incumbent agency, MediaVest.
Observers believe Walkers is exploring potential cost savings by moving its account into an Omnicom agency. It is globally aligned on the creative side to Omnicom's BBDO, with Abbott Mead Vickers BBDO handling the UK business. The US media account is held by OMD.
The majority of its £12 million spend backs TV advertising, with the remainder being allocated to press slots.
Walkers has backed a long-running campaign using Gary Lineker as the front man on its main Walkers brand. The review involves all Walkers brands.
The Lineker work was originally devised by BMP DDB in 1995. However, as part of a global centralisation of PepsiCo's business into BBDO, the Walkers brands were moved to AMV in 1998.
AMV has maintained the Lineker theme and the most recent TV spot featured Lennox Lewis in a cameo role with Lineker promoting a new variant of Walkers Squares called Squares Beefy. Walkers signed Lewis for the ad two days after his historic win over Mike Tyson.
MediaVest has received some acclaim for its work on the Walkers brief, including using the Walkers Max "naked" spot during Channel 5's infamous Naked Jungle starring Keith Chegwin.
Walkers is the biggest crisp brand in the UK with sales four times that of its nearest rival, Procter & Gamble's Pringles. It has sales of nearly £490 million a year, which equates to 11 million packs sold daily.
MediaVest, OMD and Walker Snacks all declined the opportunity to comment.