The term "franking privilege" refers to the right granted to certain members of Congress and their staff that allows free postage of official correspondence to their constituents. The member's signature, known as the "frank," serves as a substitute for the stamp on the envelope.
The 17th century British House of Commons contributed to the enactment of the franking privilege in the United States Congress. Some of the authorized users of the Frank include the Senators, Senators-Elect or Former Senators, the Vice President, the Secretary of the Senate, the Senate Legal Counsel and Senate Legislative Counsel. Abuses of the franking privilege has led to the establishment of oversight committees.