In United States politics, a ranking member is the most senior member of a congressional or state legislative committee from the minority party.^[1] On many committees the ranking minority member, along with the Chair, serve as ex officio members of all of the committee's subcommittees.

Both the United States Senate^[2] and United States House of Representatives^[3] use ranking members as part of their legislative structure.

When party control of a legislative chamber changes, a committee's ranking minority member is generally ensured to become the next chairman of the committee, and vice versa.^{[citation needed]}

Four Senate committees refer to the ranking minority member as vice chairman. The following committees follow the chairman/vice chairman structure for the majority and minority parties.

• Senate Committee on Appropriations
• Senate Committee on Indian Affairs
• Senate Select Committee on Ethics
• Senate Select Committee on Intelligence

Other Senate committees refer to the ranking minority members as ranking member.^[4]

The House of Representatives normally does not use the term vice chairman for the ranking minority member, though some committees do have a vice-chairman position, usually assigned to a senior member of the majority party other than the chairman. House committees that follow this structure are:

• House Committee on Agriculture
• House Committee on Appropriations
• House Committee on the Budget
• House Committee on Education and the Workforce
• House Committee on Energy and Commerce
• House Committee on Financial Services
• House Committee on Government Reform
• House Committee on Foreign Affairs
• House Committee on Resources
• House Committee on Veterans' Affairs
• House Permanent Select Committee on Intelligence (subcommittees only)

The position of vice chair as the designation for the ranking minority member has been used for the House January 6 Committee.

Joint committees of the House and Senate operate in much the same way, with a chairman and vice-chairman from the majority party, alternating between a member of the House and a member of the Senate, and often two ranking members from both bodies.