The service enables businesses to push updates towards users who have 'liked' them or 'checked in' to them in the past, AllThingsD reports.
Subscribers will be served adverts based on their location, the time of day and their leisure habits. Foursquare was quick to point out that all promotions will be as relevant as possible.
Promoted Updates will only appear when users open the 'Explore' tab to find places of interest nearby. The service is currently in beta with trial partners including Gap, Walgreens and Best Buy.
Foursquare launched back in 2009, and had attracted more than 10 million users by June 2011. It surpassed the milestone of 20 million users in April this year.
Foursquare is available as a free app for mobile devices or via an internet browser.