Foursquare And AmEx Expand Mobile Payments Partnership

Now there are two things American Express hopes you don’t leave home without: your card and your smartphone. The company has finalized a deal with Foursquare to offer users cash-back discounts at participating retailers when they check into a venue and spend money using their American Express cards.

The service, which got a test run at SXSW in March, launches today with retailers like H&M and Sports Authority offering discounts for spending a certain amount in their stores. Foursquare users with AmEx cards need to register their Foursquare profiles with AmEx, check into one of the participating stores, and spend the required amount of money in order to receive a credit on their next AmEx statement. H&M will give you $10 back on a $75 purchase, while Sports Authority will reimburse you $20 for spending $50.

It’s an interesting experiment in mobile payments, one in which the physical card is still very present but the mobile phone is essential to completing the transaction. It also allows American Express to ingratiate itself with perhaps a younger generation of spenders than it currently counts among its cardholders.

And the best part of the deal for AmEx? They’re not sharing any revenue with Foursquare, according to the New York Times. (An AmEx representative confirmed those terms of the deal.)

Which presents a bit of a problem for Fourquare: the check-in service is still growing strong, passing 10 million users earlier this week, and attempts by companies like Facebook and Google (NSDQ: GOOG) to muscle into its turf don’t seem to have really worked. However, it’s going to need to figure out a way to generate more revenue to be taken seriously as a business over the long haul.