Canyon County is located in the

U.S. state In the United States, a state is a constituent political entity, of which there are 50. Bound together in a political union, each state holds governmental jurisdiction over a separate and defined geographic territory where it shares its so ...

Idaho Idaho ( ) is a landlocked U.S. state, state in the Pacific Northwest and Mountain states, Mountain West subregions of the Western United States. It borders Montana and Wyoming to the east, Nevada and Utah to the south, and Washington (state), ...

. As of the 2020 Census, the population was 231,105, which by 2022 was estimated to have risen to 251,065. making it the second-most populous county in Idaho. The

county seat A county seat is an administrative center, seat of government, or capital city of a county or parish (administrative division), civil parish. The term is in use in five countries: Canada, China, Hungary, Romania, and the United States. An equiva ...

is Caldwell, and its largest city is Nampa. Canyon County is part of the

Boise metropolitan area The Boise, Idaho Metropolitan Statistical Area (MSA) (commonly known as the Boise Metropolitan Area or the Treasure Valley) is an area that encompasses Ada County, Idaho, Ada, Boise County, Idaho, Boise, Canyon County, Idaho, Canyon, Gem County, ...

History

Hudson's Bay Company The Hudson's Bay Company (HBC), originally the Governor and Company of Adventurers of England Trading Into Hudson’s Bay, is a Canadian holding company of department stores, and the oldest corporation in North America. It was the owner of the ...

established

Fort Boise Fort Boise is either of two different locations in the Western United States, both in southwestern Idaho. The first was a Hudson's Bay Company (HBC) trading post near the Snake River on what is now the Oregon border (in present-day Canyon Count ...

in 1834 near what is now

Parma Parma (; ) is a city in the northern Italian region of Emilia-Romagna known for its architecture, Giuseppe Verdi, music, art, prosciutto (ham), Parmesan, cheese and surrounding countryside. With a population of 198,986 inhabitants as of 2025, ...

, but abandoned it in 1855. Emigrants traveled through Canyon County on the

Oregon Trail The Oregon Trail was a east–west, large-wheeled wagon route and Westward Expansion Trails, emigrant trail in North America that connected the Missouri River to valleys in Oregon Territory. The eastern part of the Oregon Trail crossed what ...

. Discovery of gold in the Boise Basin in 1862 brought settlement to the region again. The lower

Boise River The Boise River is a U.S. Geological Survey. National Hydrography Dataset high-resolution flowline data. , accessed May 3, 2011 tributary of the Snake River in the Northwestern United States. It drains a rugged portion of the Sawtooth Range in so ...

was fully contained within Boise County from 1863 until the formation of Ada County in 1864. Settlement of the lower Boise River west of Boise City was limited prior to the completion of the

Oregon Short Line Railroad The Oregon Short Line Railroad was a railroad in Wyoming, Idaho, Utah, Montana and Oregon in the United States. The line was organized as the Oregon Short Line Railway in 1881 as a subsidiary of the Union Pacific Railway. The Union Pacific int ...

. Middleton was the first European settlement of Canyon County, starting in 1863. The 1870 Census for Ada County listed 76 residents of the Boise Valley, excluding Boise City and the 1880 Census listed 44 residents at Middleton. The arrival of the railroad at Caldwell led to the establishment of a town there as of August 1883. Businessmen James A. McGee and Alexander Duffes filed the plat for nearby Nampa in 1886. Parma was settled around the same time, with the Old Fort Boise post office being moved to the town's location; it was incorporated in 1904. Ada County established precincts for each of the settlements with a combined 1890 Census population of 2,311. Significant settlement of Greenleaf and Notus started around 1904 with the two settlements listed as precincts at the 1910 census. Notus was incorporated in 1921 while Greenleaf was incorporated prior to 1980. Melba was incorporated in 1912 while Wilder was incorporated in 1919. The City of Star annexed a portion of territory in northeast Canyon County prior to 2007, becoming the county's ninth incorporated city. The majority of Star is located within Ada County. The Idaho Legislature created Canyon County from Ada County in an act approved March 7, 1891, effective at the November 26, 1892, election. Caldwell was established as the county seat. The county originally contained all of Canyon and Payette counties and part of Gem; Gem County formed in 1915 and Payette County in 1917. Some sources attribute the name to the canyon of the

near Caldwell, while western writers John Rees and Vardis Fisher believed it was named for the

Snake River The Snake River is a major river in the interior Pacific Northwest region of the United States. About long, it is the largest tributary of the Columbia River, which is the largest North American river that empties into the Pacific Ocean. Begin ...

canyon, which forms a natural boundary with

Owyhee County Owyhee County ( ) is a county in the southwestern corner of the U.S. state of Idaho. As of the 2020 census, the population was 11,913. The county seat is Murphy, and its largest city is Homedale. In area it is the second-largest county in I ...

to the south and west.

Geography

According to the

United States Census Bureau The United States Census Bureau, officially the Bureau of the Census, is a principal agency of the Federal statistical system, U.S. federal statistical system, responsible for producing data about the American people and American economy, econ ...

, the county has a total area of , of which is land and (2.7%) is water.

Adjacent counties

* Payette County (north) * Gem County (northeast) * Ada County (east) *

(south) * Malheur County,

Oregon Oregon ( , ) is a U.S. state, state in the Pacific Northwest region of the United States. It is a part of the Western U.S., with the Columbia River delineating much of Oregon's northern boundary with Washington (state), Washington, while t ...

(west)

National protected areas

* Deer Flat National Wildlife Refuge (part) * Snake River Birds of Prey National Conservation Area (part)

Major highways

Interstate 84 * US 20

US 20 U.S. Route 20 or U.S. Highway 20 (US 20) is an east–west United States Highway, United States Numbered Highway that stretches from the Pacific Northwest east to New England. The "0" in its route number indicates that US 20 is a major ...

US 26 U.S. Highway 26 (US 26) is an east–west United States Numbered Highway that runs from Seaside, Oregon, to Ogallala, Nebraska. When the U.S. Numbered Highway System was first defined, it was limited to Nebraska and Wyoming Wyoming ...

US 30 U.S. Route 30 or U.S. Highway 30 (US 30) is an east–west main route of the United States Numbered Highway System, with the highway traveling across the Northern U.S. With a length of , it is the third-longest U.S. Highway, afte ...

US 95 *

SH-19 *

SH-44 *

SH-45 *

SH-55

Demographics

2010 census

As of the 2010 census, there were 188,923 people, 63,604 households, and 47,481 families living in the county. The population density was . There were 69,409 housing units at an average density of . The racial makeup of the county was 83.0% white, 1.1% American Indian, 0.8% Asian, 0.6% black or African American, 0.2% Pacific islander, 11.4% from other races, and 3.0% from two or more races. Those of Hispanic or Latino origin made up 23.9% of the population. In terms of ancestry, 18.8% were American, 17.4% were

German German(s) may refer to: * Germany, the country of the Germans and German things **Germania (Roman era) * Germans, citizens of Germany, people of German ancestry, or native speakers of the German language ** For citizenship in Germany, see also Ge ...

, 13.0% were English, and 8.8% were Irish. Of the 63,604 households, 42.7% had children under the age of 18 living with them, 56.7% were married couples living together, 12.3% had a female householder with no husband present, 25.3% were non-families, and 20.1% of all households were made up of individuals. The average household size was 2.92 and the average family size was 3.36. The median age was 31.6 years. The median income for a household in the county was $43,218 and the median income for a family was $48,219. Males had a median income of $38,132 versus $28,356 for females. The per capita income for the county was $18,366. About 12.7% of families and 17.3% of the population were below the

poverty line The poverty threshold, poverty limit, poverty line, or breadline is the minimum level of income deemed adequate in a particular country. The poverty line is usually calculated by estimating the total cost of one year's worth of necessities for ...

, including 23.8% of those under age 18 and 8.5% of those age 65 or over.

2000 census

As of the 2000 census, there were 131,441 people, 45,018 households and 33,943 families living in the county. The

population density Population density (in agriculture: Standing stock (disambiguation), standing stock or plant density) is a measurement of population per unit land area. It is mostly applied to humans, but sometimes to other living organisms too. It is a key geog ...

was . There were 47,965 housing units at an average density of . The racial makeup of the county was 83.10%

White White is the lightest color and is achromatic (having no chroma). It is the color of objects such as snow, chalk, and milk, and is the opposite of black. White objects fully (or almost fully) reflect and scatter all the visible wa ...

, 0.32%

Black Black is a color that results from the absence or complete absorption of visible light. It is an achromatic color, without chroma, like white and grey. It is often used symbolically or figuratively to represent darkness.Eva Heller, ''P ...

African American African Americans, also known as Black Americans and formerly also called Afro-Americans, are an Race and ethnicity in the United States, American racial and ethnic group that consists of Americans who have total or partial ancestry from an ...

, 0.85% Native American, 0.80% Asian, 0.13%

Pacific Islander Pacific Islanders, Pasifika, Pasefika, Pacificans, or rarely Pacificers are the peoples of the list of islands in the Pacific Ocean, Pacific Islands. As an ethnic group, ethnic/race (human categorization), racial term, it is used to describe th ...

, 12.17% from other races, and 2.62% from two or more races.

Hispanic The term Hispanic () are people, Spanish culture, cultures, or countries related to Spain, the Spanish language, or broadly. In some contexts, Hispanic and Latino Americans, especially within the United States, "Hispanic" is used as an Ethnici ...

or Latino of any race were 18.61% of the population. 15.9% were of

, 12.7% English, 10.3% American and 7.6% Irish ancestry. There were 45,018 households, of which 39.80% had children under the age of 18 living with them, 60.70% were

married couples Marriage, also called matrimony or wedlock, is a culturally and often legally recognised union between people called spouses. It establishes rights and obligations between them, as well as between them and their children (if any), and b ...

living together, 10.10% had a female householder with no husband present, and 24.60% were non-families. 19.80% of all households were made up of individuals, and 8.40% had someone living alone who was 65 years of age or older. The average household size was 2.85 and the average family size was 3.28. 30.90% of the population were under the age of 18, 10.70% from 18 to 24, 28.30% from 25 to 44, 19.10% from 45 to 64, and 11.00% who were 65 years of age or older. The median age was 30 years. For every 100 females, there were 98.70 males. For every 100 females age 18 and over, there were 96.30 males. The

median household income The median income is the income amount that divides a population into two groups, half having an income above that amount, and half having an income below that amount. It may differ from the mean (or average) income. Both of these are ways of und ...

was $35,884 and the median family income was $40,377. Males had a median income of $29,418 compared with $22,044 for females. The

per capita income Per capita income (PCI) or average income measures the average income earned per person in a given area (city, region, country, etc.) in a specified year. In many countries, per capita income is determined using regular population surveys, such ...

for the county was $15,155. About 8.70% of families and 12.00% of the population were below the

, including 14.50% of those under age 18 and 10.70% of those age 65 or over.

Communities

Cities

* Caldwell * Greenleaf * Melba * Middleton * Nampa *

Notus In Greek mythology and religion, Notus () is the god of the south wind and one of the Anemoi (wind-gods), sons of the dawn goddess Eos and the star-god Astraeus. A desiccating wind of heat, Notus was associated with the storms of late summer and ...

Star A star is a luminous spheroid of plasma (physics), plasma held together by Self-gravitation, self-gravity. The List of nearest stars and brown dwarfs, nearest star to Earth is the Sun. Many other stars are visible to the naked eye at night sk ...

(partially) * Wilder

Unincorporated communities

* Bowmont * Huston * Roswell * Sunnyslope * Walters Ferry, Idaho

Politics

Like the majority of Idaho, Canyon County is reliably Republican by comfortable margins. The last time a Democratic candidate carried the county was in

1936 Events January–February * January 20 – The Prince of Wales succeeds to the throne of the United Kingdom as King Edward VIII, following the death of his father, George V, at Sandringham House. * January 28 – Death and state funer ...

Franklin D. Roosevelt Franklin Delano Roosevelt (January 30, 1882April 12, 1945), also known as FDR, was the 32nd president of the United States, serving from 1933 until his death in 1945. He is the longest-serving U.S. president, and the only one to have served ...

. In elections, Republican candidates usually achieve approximately two-thirds of the vote from Canyon County.

Education

School districts include: * Caldwell School District 132 * Homedale Joint School District 370 * Kuna Joint School District 3 * Marsing Joint School District 363 * Melba Joint School District 136 * Middleton School District 134 * Nampa School District 131 * Notus School District 135 * Parma School District 137 * Vallivue School District 139 * West Ada School District (Meridian Joint School District 2) * Wilder School District 133 Residents are in the area (and the taxation zone) for

College of Western Idaho College of Western Idaho (CWI) is a public community college in Southwest Idaho with its primary campus locations in Boise and Nampa. CWI also offers classes at several community locations throughout the Treasure Valley. It is one of four c ...

Healthcare

The county is served by the Southwest Idaho Health District.

References

External links

* - Canyon County *
Western Canyon Chronicle
' - Official newspaper for Parma, Notus, Wilder & Greenleaf, in Canyon County, Idaho {{coord, 43.63, -116.71, display=title, type:adm2nd_region:US-ID_source:UScensus1990 Idaho counties 1891 establishments in Idaho Boise metropolitan area Populated places established in 1891