Montana counties

Every county in Montana, with the ZIP codes recorded in each. Pick one to see its full ZIP code list.

counties: 56
ZIP codes: 404

All Montana counties

Every Montana county with the number of ZIP codes it holds and the city holding the most of them.
County	ZIP codes	Largest city
Beaverhead County	8	Dell
Big Horn County	10	Busby
Blaine County	7	Chinook
Broadwater County	4	Radersburg
Carbon County	10	Bearcreek
Carter County	5	Alzada
Cascade County	18	Great Falls
Chouteau County	7	Big Sandy
Custer County	4	Ismay
Daniels County	4	Flaxville
Dawson County	4	Bloomfield
Deer Lodge County	2	Anaconda
Fallon County	3	Baker
Fergus County	10	Buffalo
Flathead County	18	Kalispell
Gallatin County	13	Bozeman
Garfield County	5	Brusett
Glacier County	4	Babb
Golden Valley County	2	Lavina
Granite County	3	Drummond
Hill County	7	Box Elder
Jefferson County	6	Basin
Judith Basin County	5	Geyser
Lake County	12	Arlee
Lewis and Clark County	15	Helena
Liberty County	3	Chester
Lincoln County	7	Eureka
Madison County	11	Alder
McCone County	3	Brockway
Meagher County	3	Martinsdale
Mineral County	6	Alberton
Missoula County	16	Missoula
Musselshell County	4	Roundup
Park County	9	Clyde Park
Petroleum County	2	Teigen
Phillips County	6	Dodson
Pondera County	6	Brady
Powder River County	5	Biddle
Powell County	7	Avon
Prairie County	3	Fallon
Ravalli County	10	Conner
Richland County	5	Crane
Roosevelt County	7	Bainville
Rosebud County	11	Ashland
Sanders County	9	Dixon
Sheridan County	9	Antelope
Silver Bow County	8	Butte
Stillwater County	8	Absarokee
Sweet Grass County	4	Big Timber
Teton County	6	Bynum
Toole County	8	Ethridge
Treasure County	3	Bighorn
Valley County	11	Fort Peck
Wheatland County	4	Harlowton
Wibaux County	1	Wibaux
Yellowstone County	23	Billings

Scope every county-equivalent recorded in Montana. Source Census 2024 county Gazetteer (2024 Gazetteer) and GeoNames US postal codes (2026-07 postal dump). Updated 15 July 2026. Names and boundaries follow the Census Bureau's current county-equivalent set, not the MT postal source's older names.