The FTC's Bureau of Competition requested the company to provide information regarding violations of the Durbin amendment, Visa said in its annual 10-K filing with the U.S. Securities and Exchange Commission on Friday,
The Durbin amendment, a part of the Dodd-Frank Act of 2010, lowered swipe fees that are charged by merchants every time a consumer makes a purchase using a debit card.
The voluntary access letter was issued by the FTC on September 21 and the request focuses on information "related to the purposes, implementation, and impact of the optional PIN Debit Gateway Service", Visa said in the filing.
However, the revenue generated by the service is not material to the company's financial statements, Visa said.
The company disclosed in a May regulatory filing that the U.S. Department of Justice had asked for documents and information about its response to a new law and rules limiting debit card fees.
Visa introduced a new fee structure in April called Fixed Acquirer Network Fee to push more transactions to its network that is likely to hurt other card processors.
Shares of Visa were up more than 1 percent to $142.20 in afternoon trade on the New York Stock Exchange.
(Reporting by Aman Shah and Sharanya Hrishikesh in Bangalore; Editing by Anil D'Silva)