Montana Beaverhead County Big Horn County Blaine County Broadwater County Carbon County Carter County Cascade County Chouteau County Custer County Daniels County Dawson County Deer Lodge County Fallon County Fergus County Flathead County Gallatin County Garfield County Glacier County Golden Valley County Granite County Hill County Jefferson County Judith Basin County Lake County Lewis and Clark County Liberty County Lincoln County McCone County Madison County Meagher County Mineral County Missoula County Musselshell County Park County Petroleum County Phillips County Pondera County Powder River County Powell County Prairie County Ravalli County Richland County Roosevelt County Rosebud County Sanders County Sheridan County Silver Bow County Stillwater County Sweet Grass County Teton County Toole County Treasure County Valley County Wheatland County Wibaux County Yellowstone County Billings MSA Great Falls MSA Missoula MSA

MSAs = Metropolitan Statistical Areas.  Each of the three MSAs in Montana - Billings, Great Falls and Missoula - is a single-county entity and has the same boundaries as the respective county.