Idaho (/ˈaɪdəhoʊ/ ^ⓘ, EYE-də-hoe) is a landlocked state in the Pacific Northwest and Mountain West subregions of the Western United States. It borders Montana and Wyoming to the east, Nevada and Utah to the south, and Washington and Oregon to the west; the state shares a small portion of the Canada–United States border to the north with the Canadian province of British Columbia. Idaho's state capital and largest city is Boise. With an area of 83,569 square miles (216,440 km²), Idaho is the 14th-largest state by land area. The state has a population of approximately two million people; it ranks as the 13th-least populous and the seventh-least densely populated of the 50 U.S. states.

Idaho
State
Flag Seal
Nicknames:  The Gem State (official), The Potato State
Motto:  Esto perpetua (Latin for "Let it be perpetual")
Anthem: "Here We Have Idaho"
Location of Idaho within the United States
Country	United States
Before statehood	Oregon Territory, Washington Territory, Idaho Territory
Admitted to the Union	July 3, 1890 (43rd)
Capital (and largest city)	Boise
Largest county or equivalent	Ada
Largest metro and urban areas	Boise
Government
• Governor	Brad Little (R)
• Lieutenant Governor	Scott Bedke (R)
Legislature	Legislature
• Upper house	Senate
• Lower house	House of Representatives
Judiciary	Idaho Supreme Court
U.S. senators	Mike Crapo (R) Jim Risch (R)
U.S. House delegation	1. Russ Fulcher (R) 2. Mike Simpson (R) (list)
Area
• Total	83,569 sq mi (216,444 km2)
• Land	82,644 sq mi (214,046 km2)
• Water	926 sq mi (2,399 km2)  1.11%
• Rank	11th
Dimensions
• Length	479 mi (771 km)
• Width	305 mi (491 km)
Elevation	4,990 ft (1,520 m)
Highest elevation (Borah Peak)	12,661 ft (3,859 m)
Lowest elevation (Confluence of Snake and Clearwater River; Lewiston)	712 ft (217 m)
Population  (2025)
• Total	2,029,733
• Rank	37th
• Density	21.6/sq mi (8.33/km2)
• Rank	44th
• Median household income	$74,900 (2023)
• Income rank	24th
Demonym	Idahoan
Language
• Official language	English
Time zones
primary	UTC−07:00 (Mountain)
• Summer (DST)	UTC−06:00 (MDT)
Idaho Panhandle	UTC−08:00 (Pacific)
• Summer (DST)	UTC−07:00 (PDT)
USPS abbreviation	ID
ISO 3166 code	US-ID
Latitude	42° N to 49° N
Longitude	111°03′ W to 117°15′ W
Website	idaho.gov

For thousands of years, and prior to European colonization, Idaho had been inhabited by natives. In the early 19th century, Idaho was considered part of the Oregon Country, an area which was disputed between the U.S. and the British Empire. Idaho officially became a U.S. territory with the signing of the Oregon Treaty of 1846, but a separate Idaho Territory was not organized until 1863, instead being included for periods in Oregon Territory and Washington Territory. The state was eventually admitted to the Union on July 3, 1890, becoming the 43rd state.

Forming part of the Pacific Northwest (and the associated Cascadia bioregion), Idaho is divided into several distinct geographic and climatic regions. The state's north, the relatively isolated Idaho Panhandle, is closely linked with Eastern Washington, with which it shares the Pacific Time Zone—the rest of the state uses the Mountain Time Zone. The state's south includes the Snake River Plain (which has most of the population and agricultural land), and the southeast incorporates part of the Great Basin. Idaho is quite mountainous and contains several stretches of the Rocky Mountains. The United States Forest Service holds about 38% of Idaho's land, the highest proportion of any state.

Industries significant for the state economy include manufacturing, agriculture, mining, forestry, science and technology, and tourism. Idaho has been a predominantly Republican state since statehood, with the Republican Party dominating in both state and national elections; abortion is severely restricted and the state retains the death penalty, including methods like the firing squad. The state contains the Idaho National Laboratory. Idaho's agricultural sector supplies many products, but the state is best known for its potato crop, which comprises around one-third of the nationwide yield. Its official state nickname is the "Gem State".