The United States District Court for the District of Montana (in case citations, D. Mont.) is the United States District Court whose jurisdiction is the state of Montana (except the part of the state within Yellowstone National Park, which is under the jurisdiction of the United States District Court for the District of Wyoming).^[1][2] The court is located in Billings, Butte, Great Falls, Helena and Missoula.

Cases from the District of Montana are appealed to the United States Court of Appeals for the Ninth Circuit (except for patent claims and claims against the U.S. government under the Tucker Act, which are appealed to the Federal Circuit).

The United States Attorney's Office for the District of Montana represents the United States in civil and criminal litigation in the court.

The District of Montana was organized on February 22, 1889, by 25 Stat. 676, following Montana's admission to statehood. Congress organized Montana as a single judicial district, and authorized one judgeship for the district court, which was assigned to the Ninth Circuit. A temporary second judgeship was added on September 14, 1922, by 42 Stat. 837, and was made permanent on May 31, 1938, by 52 Stat. 584. On July 10, 1984, by 98 Stat. 333, the third judgeship was authorized.^[3]

As of August 31, 2023^[update]:

Chief judges have administrative responsibilities with respect to their district court. Unlike the Supreme Court, where one justice is specifically nominated to be chief, the office of chief judge rotates among the district court judges. To be chief, a judge must have been in active service on the court for at least one year, be under the age of 65, and have not previously served as chief judge.

A vacancy is filled by the judge highest in seniority among the group of qualified judges. The chief judge serves for a term of seven years, or until age 70, whichever occurs first. The age restrictions are waived if no members of the court would otherwise be qualified for the position.

When the office was created in 1948, the chief judge was the longest-serving judge who had not elected to retire, on what has since 1958 been known as senior status, or declined to serve as chief judge. After August 6, 1959, judges could not become or remain chief after turning 70 years old. The current rules have been in operation since October 1, 1982.

• Courts of Montana
• List of current United States district judges
• List of United States federal courthouses in Montana
• United States Court of Appeals for the Ninth Circuit