Puerto Rico's largest bank, Banco Popular, will now be compatible with Samsung Pay. Customers with Samsung Pay-compatible devices on Sprint, AT&T, T-Mobile, and Claro will be able to add eligible cards from Banco Popular to their Samsung Pay accounts. Samsung Pay is the only mobile service that lets mobile phones pay at NFC terminals as well as MST (Magnetic Secure Transmission) which mimics a card swipe and is compatible with virtually any card terminal that uses a magnetic strip reader. Here is a list of phones compatible with Samsung Pay in Puerto Rico: Galaxy...
Source: http://www.gsmarena.com/samsung_pay_launching_in_puerto_rico_w__banco_popular-news-19364.php