The deal sees Walker working alongside M & C Saatchi from May this year as media planners and buyers.
Ian McLeod, Halfords Trading Director said: "We now look forward to working with M & C Saatchi and Walker Media on delivery of a new direction in the communication of the Halfords brand."
David Kershaw, partner with M & C Saatchi said: "We are looking forward to creating advertising which fully supports the next stage of Halfords growth."
Full story in tomorrow's print edition of Media Week.