Following a 16-month trial to stock branded FMCG goods, M&S will now sell a range of 400 brands including Coca Cola, Heinz, Kellogg and Marmite at all UK stores.
Products will fill gaps in brand-dominated categories where M&S “could simply never compete” and typically has low market share or no own-brand equivalent.
Sir Stuart Rose says selling branded products will be “much more convenient for our customers to get what they need without going elsewhere”.
In its half-year trading statement, M&S reported 2.8% sales growth to £4.3bn, driven by “new products, better values and innovation”.
The retailer claims it has also improved its multichannel offer, in-store service and international operations.
Pre-tax profit at the high street chain remained flat at £306.7m, while adjusted profit before tax was up on last year at £298.3m.
Food sales were up 1.8% boosted by investment in prices and promotions such as Wise Buys, and meal deals.
Sir Stuart Rose, M&S chairman, says the company “remains cautious” about Christmas trading and the year ahead.
Yesterday, the chain revealed its star-studded Christmas advertising campaign, starring Stephen Fry, Joanna Lumley and Twiggy among others.