Booth has been replaced by Anjum Ahmed who also oversees design at the kitchen company; Ahmed now has the combined role of design and marketing director.
It is not known whether media incumbent Universal McCann Manchester will be invited to repitch.
The lion's share of Magnet's marketing focuses on special offers and discounts supported by tactical TV and press campaigns.
In April the retailer ran a nationwide competition to find the kitchen most in need of a makeover. The promotion was in response to the growing number of DIY disasters created by consumers inspired by TV home-make-over shows. Consumers were asked to send pictures of their own kitchen to the Magnet website. The one voted the biggest disaster won a £10,000 Magnet makeover.
Magnet would not comment on the review.