McCann will defend its 16-year hold on the account against three other undisclosed agencies. These are said to include two regional shops and one from London.
The review follows what has been described as a lacklustre Christmas performance from the retailer - senior executives fear that its advertising has become too anonymous.
Magnet's media assignment will remain with Universal McCann Manchester.
Magnet executives led by Nick Booth, the company's brand marketing manager, have spent the past two months talking to agencies before finalising their shortlist. Pitches will take place within the next six weeks.
For McCann, the review is the latest of a series of repitches which have threatened its tenure of the business.
Magnet, which is part of the Nobia Group, one of the biggest kitchen companies in Europe, has more than 200 showrooms throughout the UK and employs more than 1,700 people.
The review comes as Magnet faces intensified competition from the DIY "sheds". As a result, its advertising has been heavily price-led.
"It's a frustrating account to work on," an industry source said. "The company is preoccupied with footfall and almost permanent 'sales'. It has never really tried to underpin its brand with a strategy and this can wear agencies down."
Magnet enjoyed a 13 per cent jump in kitchen sales last year and saw its operating profit climb by 47 per cent to £27.7 million.