Stamford-based Patriot Bank has acquired a portfolio of prepaid debit card deposits, a move that the bank said would increase its net interest margin.

Patriot Bank has closed on the deal to acquire the cards from a national provider and processor of prepaid debit cards for corporate, consumer and government clients. Patriot did not reveal the seller’s name.

The card portfolio has a total balance of approximately $52 million, and the bank said in a statement that the balance is expected to grow over time.

With the closing of the transaction, Patriot becomes the depository and issuing bank for these prepaid cards. The bank will verify and control funds going in and out from card usage, and it will also provide controls, oversight, and monitoring to ensure that merchants’ banks receive payments through the network. Patriot will also verify that customers’ deposits in various cash networks are routed to the correct debit card account.

Patriot received authorization from the Office of the Controller of the Currency to acquire the cards. The bank said its overall cost of funds would decrease as a result of the transaction, which it said is “a meaningful enhancement to the bank’s deposit gathering strategy and ongoing profitability.”

“We’re pleased to have successfully completed the bank’s first, value-enhancing prepaid card transaction, which is a pivotal move towards the bank’s longer-term deposit gathering strategy and will increase the bank’s net interest margin,” Michael Carrazza, Patriot chairman, said in the statement. “Our expansion into this finance sector further enhances Patriot’s brand and broadens the services we can deliver to our banking clients.”