Channel 4 and Hollyoaks' production company Lime Pictures have secured a six-month deal with the firm, Broadcast reports.
L'Oréal products will now appear in a number of settings on the show, including at the village's gym. They may also feature on adverts displayed on the local bus stop.
The deal was brokered by media agency ZenithOptimedia, Channel 4's sponsorship, placement and funded content business manager Vicky Kell, Channel 4's partnership lead Rob Ramsay and Lime Pictures' managing director Sean Marley.
Product placement for Hollyoaks was first planned some time ago as Channel 4 reportedly identified £12 million worth of placement opportunities within the teen soap last summer. The opportunities covered six areas, including fashion, health and beauty and coffee/retail.
Coronation Street last year became the first UK soap to feature product placement as a Nationwide cash machine was brought into Dev Alahan's corner shop. The Nationwide deal has since been renewed for another year.
Product placement was given the green light by Ofcom in December 2010.
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