This is a list of the 56 counties in the U.S. state

U.S. state

A U.S. state is any one of the 50 federated states of the United States of America that share sovereignty with the federal government. Because of this shared sovereignty, an American is a citizen both of the federal entity and of his or her state of domicile. Four states use the official title of...

 of Montana

Montana

Montana is a state in the Western United States. The western third of Montana contains numerous mountain ranges. Smaller, "island ranges" are found in the central third of the state, for a total of 77 named ranges of the Rocky Mountains. This geographical fact is reflected in the state's name,...

. Montana has two consolidated city-counties—Anaconda

Anaconda, Montana

Anaconda, county seat of Anaconda City/Deer Lodge County, is located in mountainous southwestern Montana. The Continental Divide passes within 8 miles of the community with the local Pintler Mountain range reaching 10,379 feet...

 with Deer Lodge County

Deer Lodge County, Montana

-National protected areas:*Beaverhead National Forest *Deerlodge National Forest -Demographics:As of the census of 2000, there were 9,417 people, 3,995 households, and 2,524 families residing in the county. The population density was 13 people per square mile . There were 4,958 housing units at an...

 and Butte

Butte, Montana

Butte is a city in Montana and the county seat of Silver Bow County, United States. In 1977, the city and county governments consolidated to form the sole entity of Butte-Silver Bow. As of the 2010 census, Butte's population was 34,200...

 with Silver Bow County

Silver Bow County, Montana

-National protected areas:*Beaverhead National Forest *Deerlodge National Forest -Demographics:As of the census of 2000, there were 34,606 people, 14,432 households, and 8,933 families residing in the county. The population density was 48 people per square mile . There were 16,176 housing units at...

. The portion of Yellowstone National Park

Yellowstone National Park

Yellowstone National Park, established by the U.S. Congress and signed into law by President Ulysses S. Grant on March 1, 1872, is a national park located primarily in the U.S. state of Wyoming, although it also extends into Montana and Idaho...

 that lies within Montana was not part of any county until 1978, when part of it was nominally added to Gallatin County

Gallatin County, Montana

-National protected areas:* Gallatin National Forest * Yellowstone National Park -Demographics:As of the census of 2000, there were 67,831 people, 26,323 households, and 16,188 families residing in the county. The population density was 26 people per square mile . There were 29,489 housing units...

, and the rest of it to Park County

Park County, Montana

Park Counties in Montana and Wyoming are among the very few pairs of counties in the United States with the same name to border each other across state lines.-National protected areas:* Custer National Forest * Gallatin National Forest...

.

Montana's postal abbreviation is MT and its FIPS state code

FIPS state code

FIPS state codes were numeric and two-letter alphabetic codes defined in U.S. Federal Information Processing Standard Publication 5-2 to identify U.S. states and certain other associated areas...

 is 30.

Counties

The Federal Information Processing Standard

Federal Information Processing Standard

A Federal Information Processing Standard is a publicly announced standardization developed by the United States federal government for use in computer systems by all non-military government agencies and by government contractors, when properly invoked and tailored on a contract...

 (FIPS) code, which is used by the United States government to uniquely identify counties, is provided for each county. The FIPS code for each county links to census data for that county.

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Defunct County

• Yellowstone National Park
  Yellowstone National Park (part), Montana
  Yellowstone National Park was a former county-equivalent in the state of Montana, United States. Its territory was and is the Montana portion of Yellowstone National Park. Its total area is 637.42 km² , with 635.54 km² of land and 1.884 km² of water...
  
  (1872–1978)