Orders for business records from the surveillance court generally prohibit recipients from talking about them. A spokeswoman for one large company that handles money transfers abroad, Western Union, did not directly address a question about whether it had been ordered to turn over records in bulk, but said that the company complies with legal requirements to provide information.

“We collect consumer information to comply with the Bank Secrecy Act and other laws,” said the spokeswoman, Luella Chavez D’Angelo. “In doing so, we also protect our consumers’ privacy.”

In recent months, there have been hints in congressional testimony, declassified documents and litigation that the N.S.A. program — which was disclosed by Edward J. Snowden, a former N.S.A. contractor — is not unique in collecting records involving Americans.

For example, the American Civil Liberties Union is fighting a Freedom of Information Act lawsuit for documents related to Section 215 of the Patriot Act, the provision that allows the government to compel companies to turn over business records for counterterrorism purposes. After the government declassified the N.S.A. phone records program, it has released many documents about it in response to the suit.

But the government has notified the A.C.L.U. that it is withholding two Foreign Intelligence Surveillance Court rulings invoking Section 215 — one dated Aug. 20, 2008, and the other Nov. 23, 2010 — because they discuss matters that remain classified, according to Alexander Abdo, an A.C.L.U. lawyer. “It suggests very strongly that there are other programs of surveillance that the public has a right to know about,” Mr. Abdo said.

In addition, a Justice Department “white paper” on the N.S.A.’s call records program, released in August, said that communications logs are “a context” in which the “collection of a large volume of data” is necessary for investigators to be able to analyze links between terrorism suspects and their associates. It did not say that call records are the only context that meets the criteria for bulk gathering.

In hearings on Capitol Hill, government officials have repeatedly avoided saying that phone logs — which include date, duration and numbers of phone calls, but not their content — are the only type of data that would qualify for bulk collection under the Patriot Act provision. In a little-noticed exchange late in an Oct. 3 hearing before the Senate Judiciary Committee, Gen. Keith B. Alexander, the N.S.A. director, appeared to go further.