Idaho County Maps: Interactive History & Complete List

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County Map of Idaho
Map of Idaho county boundaries and county seats

Maps of Idaho are a very helpful tool when it comes to genealogy and family tree research, notably in the event that you live far away from where your ancestor lived.

Given that Idaho’s political borders have often changed over the years, historic maps can be crucial in helping you find out the exact location of your ancestor’s hometown, just what land they owned, who his or her neighbors were, and much more besides.

Maps of Idaho are an excellent way of getting started with your research since they provide valuable information and facts immediately and present them in a clear and easily understandable format.

Idaho borders Montana, Nevada, Oregon, Utah, Washington, Wyoming, and Canada. Idaho’s 10 largest cities are Boise, Nampa, Meridian, Idaho Falls, Pocatello, Caldwell, Coeur d’Alene, Twin Falls, Lewiston, and Post Falls.

Learn more historical facts about Idaho counties here.

Interactive Map of Idaho County Formation History

AniMap Plus 3.0, with the permission of the Goldbug Company

List of Every Idaho County

Ada County

Established in 1864, Ada County is the most populous county in Idaho with over 481,000 residents. It is home to the state capital, Boise.

Adams County

Founded in 1911, Adams County has a population of around 4,000. The county seat is Council.

Bannock County

Established in 1893, Bannock County is home to over 87,000 people. The county seat is Pocatello.

Bear Lake County

Bear Lake County has a population of around 6,000 and was founded in 1875. The county seat is Paris.

Benewah County

Established in 1915, Benewah County has around 9,000 residents. The county seat is St. Maries.

Bingham County

Founded in 1885, Bingham County has a population of over 46,000. The county seat is Blackfoot.

Blaine County

Established in 1895, Blaine County has a population of approximately 22,000. The county seat is Hailey.

Boise County

Boise County is home to around 7,500 people and was established in 1864. The county seat is Idaho City.

Bonner County

Founded in 1907, Bonner County has over 45,000 residents. The county seat is Sandpoint.

Bonneville County

Established in 1911, Bonneville County has a population of over 119,000. The county seat is Idaho Falls.

Boundary County

Founded in 1915, Boundary County has a population of around 12,000. The county seat is Bonners Ferry.

Butte County

Butte County is home to around 2,500 people and was established in 1917. The county seat is Arco.

Camas County

Established in 1917, Camas County has a population of around 1,000. The county seat is Fairfield.

Canyon County

Founded in 1891, Canyon County has a population of over 225,000. The county seat is Caldwell.

Caribou County

Established in 1919, Caribou County has around 7,000 residents. The county seat is Soda Springs.

Cassia County

Founded in 1879, Cassia County has a population of over 24,000. The county seat is Burley.

Clark County

Clark County has a population of around 870 and was established in 1919. The county seat is Dubois.

Clearwater County

Established in 1911, Clearwater County is home to around 8,000 people. The county seat is Orofino.

Custer County

Founded in 1881, Custer County has a population of around 4,100. The county seat is Challis.

Elmore County

Established in 1889, Elmore County has over 27,000 residents. The county seat is Mountain Home.

Franklin County

Founded in 1913, Franklin County has a population of around 13,000. The county seat is Preston.

Fremont County

Established in 1893, Fremont County is home to around 13,000 people. The county seat is St. Anthony.

Gem County

Gem County has a population of around 18,000 and was established in 1915. The county seat is Emmett.

Gooding County

Founded in 1913, Gooding County has a population of approximately 15,000. The county seat is Gooding.

Idaho County

Established in 1864, Idaho County is home to around 17,000 people. The county seat is Grangeville.

Jefferson County

Jefferson County was established in 1913 and has a population of over 29,000. The county seat is Rigby.

Jerome County

Founded in 1919, Jerome County has over 24,000 residents. The county seat is Jerome.

Kootenai County

Established in 1864, Kootenai County has a population of over 170,000. The county seat is Coeur d’Alene.

Latah County

Latah County has a population of around 40,000 and was established in 1888. The county seat is Moscow.

Lemhi County

Established in 1869, Lemhi County has around 8,000 residents. The county seat is Salmon.

Lewis County

Founded in 1911, Lewis County has a population of around 3,500. The county seat is Nezperce.

Lincoln County

Established in 1895, Lincoln County has a population of approximately 5,200. The county seat is Shoshone.

Madison County

Founded in 1913, Madison County has a population of over 39,000. The county seat is Rexburg.

Minidoka County

Established in 1913, Minidoka County is home to over 20,000 people. The county seat is Rupert.

Nez Perce County

Nez Perce County was established in 1861 and has a population of around 40,000. The county seat is Lewiston.

Oneida County

Founded in 1864, Oneida County has around 4,400 residents. The county seat is Malad City.

Owyhee County

Established in 1863, Owyhee County has a population of around 12,000. The county seat is Murphy.

Payette County

Founded in 1917, Payette County has a population of approximately 24,000. The county seat is Payette.

Power County

Power County has a population of around 7,400 and was established in 1913. The county seat is American Falls.

Shoshone County

Established in 1864, Shoshone County is home to around 12,000 people. The county seat is Wallace.

Teton County

Teton County has around 12,000 residents and was established in 1915. The county seat is Driggs.

Twin Falls County

Founded in 1907, Twin Falls County has a population of over 85,000. The county seat is Twin Falls.

Valley County

Established in 1917, Valley County has a population of around 12,000. The county seat is Cascade.

Washington County

Washington County was established in 1879 and is home to around 10,000 people. The county seat is Weiser.

Old Antique Atlases & Maps of Idaho

Disclaimer: All Idaho maps are free to use for your own genealogical purposes and may not be reproduced for resale or distribution.

Source: David Rumsey Historical Map Collection

  • 1880 Territory of Idaho

    1880 Idaho

    1880 Territory of Idaho

  • 1880 Map Of Idaho

    1880 Map Of Idaho

    1880 Map of Oregon, Washington, Idaho, and part of Montana

Idaho Map Links

Caleb Pike
About the author

Caleb Pike is an avid hiker and nature lover, with a passion for exploring the great outdoors. He's a writer, photographer, and adventurer, always seeking new trails to blaze and peaks to conquer.