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Pima County, Arizona facts for kids

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Pima County
Pima County Courthouse
Pima County Courthouse
Official seal of Pima County
Map of Arizona highlighting Pima County
Location within the U.S. state of Arizona
Map of the United States highlighting Arizona
Arizona's location within the U.S.
Country  United States
State  Arizona
Founded November 9, 1864
Named for Pima people
Seat Tucson
Largest city Tucson
 • Total 9,189 sq mi (23,800 km2)
 • Land 9,187 sq mi (23,790 km2)
 • Water 2.1 sq mi (5 km2)  0.02%%
 • Total 1,043,433
 • Density 113.552/sq mi (43.8428/km2)
Time zone UTC−7 (Mountain)
Congressional districts 1st, 2nd, 3rd
Pima County Fair
Pima County Fair, 2007

Pima County ( PEE-mə) is a county in the south central region of the U.S. state of Arizona. As of the 2020 census, the population was 1,043,433, making it Arizona's second-most populous county. The county seat is Tucson, where most of the population is centered. The county is named after the Pima Native Americans who are indigenous to this area.

Pima County includes the entirety of the Tucson Metropolitan Statistical Area, and it is the third largest metropolitan area in the Southwestern United States.

Pima County contains parts of the Tohono O'odham Nation, as well as all of the San Xavier Indian Reservation, the Pascua Yaqui Indian Reservation, Organ Pipe Cactus National Monument, Ironwood Forest National Monument and Saguaro National Park.

The vast majority of the county population lies in and around the city of Tucson (2017 city population: 535,677), filling much of the eastern part of the county with urban development. Tucson, Arizona's second largest city, is a major commercial and academic center. Other urban areas include the Tucson suburbs of Marana (population 44,792), Oro Valley (population 44,350), Sahuarita (population 29,318), and South Tucson (population 5,643), a large ring of unincorporated urban development, and the growing satellite town Green Valley. The rest of the county is sparsely populated; the largest towns are Sells, the capital of the Tohono O'odham Nation, and Ajo in the county's far western region.


Pima County, one of the four original counties in Arizona, was created by the 1st Arizona Territorial Legislature with land acquired through the Gadsden Purchase from Mexico in 1853. The original county consisted of all of Arizona Territory east of longitude 113° 20' and south of the Gila River. Soon thereafter, the counties of Cochise, Graham and Santa Cruz were carved from the original Pima County.


According to the U.S. Census Bureau, the county has a total area of 9,189 square miles (23,800 km2), of which 9,187 square miles (23,790 km2) is land and 2.1 square miles (5.4 km2) (0.02%) is water.

Topographic features

Major highways

Adjacent counties and municipalities

National protected areas

Sonoran Desert Conservation Plan

The award-winning Sonoran Desert Conservation Plan (SDCP) is Pima County’s plan for balancing the conservation and protection of our cultural and natural resource heritage with our efforts to maintain an economically vigorous and fiscally responsible community. Broadly defined, the SDCP considered the following elements: critical habitats and biological corridors, riparian areas, mountain parks, historical and cultural preservation, and ranch conservation. All five elements, along with fiscal analysis, were critical in forming a viable land management plan for Pima County.


Historical population
Census Pop.
1870 5,716
1880 17,006 197.5%
1890 12,673 −25.5%
1900 14,689 15.9%
1910 22,818 55.3%
1920 34,680 52.0%
1930 55,676 60.5%
1940 72,838 30.8%
1950 141,216 93.9%
1960 265,660 88.1%
1970 351,667 32.4%
1980 531,443 51.1%
1990 666,880 25.5%
2000 843,746 26.5%
2010 980,263 16.2%
2020 1,043,433 6.4%
U.S. Decennial Census
1790–1960 1900–1990
1990–2000 2010–2018 2020 census

2010 census

As of the 2010 census, there were 980,263 people, 388,660 households, and 243,167 families living in the county. The population density was 106.7 inhabitants per square mile (41.2/km2). There were 440,909 housing units at an average density of 48.0 per square mile (18.5/km2). The racial makeup of the county was 74.3% white, 3.5% black or African American, 3.3% American Indian, 2.6% Asian, 0.2% Pacific islander, 12.3% from other races, and 3.7% from two or more races. Those of Hispanic or Latino origin made up 34.6% of the population.

The largest ancestry groups were:

  • 30.8% Mexican
  • 16.2% German
  • 10.6% Irish
  • 9.9% English
  • 4.5% Italian
  • 3.1% French
  • 2.8% American
  • 2.7% Polish
  • 2.4% Scottish
  • 1.8% Scotch-Irish
  • 1.7% Norwegian
  • 1.6% Dutch
  • 1.6% Swedish
  • 1.1% Russian

Of the 388,660 households, 29.8% had children under the age of 18 living with them, 44.5% were married couples living together, 12.8% had a female householder with no husband present, 37.4% were non-families, and 29.2% of all households were made up of individuals. The average household size was 2.46 and the average family size was 3.06. The median age was 37.7 years.

The median income for a household in the county was $45,521 and the median income for a family was $57,377. Males had a median income of $42,313 versus $33,487 for females. The per capita income for the county was $25,093. About 11.2% of families and 16.4% of the population were below the poverty line, including 22.6% of those under age 18 and 8.5% of those age 65 or over.

Metropolitan Statistical Area

The United States Office of Management and Budget has designated Pima County as the Tucson, AZ Metropolitan Statistical Area. The United States Census Bureau ranked the Tucson, AZ Metropolitan Statistical Area as the 53rd most populous metropolitan statistical area of the United States as of July 1, 2012.

The Office of Management and Budget has further designated the Tucson, AZ Metropolitan Statistical Area as a component of the more extensive Tucson-Nogales, AZ Combined Statistical Area, the 53rd most populous combined statistical area and the 59th most populous primary statistical area of the United States as of July 1, 2012.


Pima County Incorporated and Unincorporated areas
Map of the incorporated and unincorporated cities and towns in Pima County. Also shown are the borders for the Indian Reservations in the county.
Pima Co. Copper mines
Astronaut photo of the open-pit copper mines adjacent to Green Valley, 2010. Note that north is to the left.



Census-designated places

Indian reservations

Other communities

County population ranking

The population ranking of the following table is based on the 2010 census of Pima County.

county seat

Rank City/Town/etc. Population (2010 Census) Municipal type Incorporated
1 Tucson 520,116 City 1775
2 Casas Adobes 66,795 CDP
3 Catalina Foothills 50,796 CDP
4 Oro Valley 41,011 Town 1974
5 Marana 34,961 Town 1977
6 Drexel Heights 27,749 CDP
7 Sahuarita 25,259 Town 1994
8 Green Valley 21,391 CDP
9 Tanque Verde 16,901 CDP
10 Flowing Wells 16,419 CDP
11 Tucson Estates 12,192 CDP
12 Vail 10,208 CDP
13 Picture Rocks 9,563 CDP
14 Valencia West 9,355 CDP
15 Catalina 7,569 CDP
16 Avra Valley 6,050 CDP
17 Corona de Tucson 5,675 CDP
18 South Tucson 5,652 City 1940
19 Three Points 5,581 CDP
20 Summit 5,372 CDP
21 Rincon Valley 5,139 CDP
22 Ajo 3,304 CDP
23 Sells 2,495 CDP
24 Arivaca Junction 1,090 CDP
25 Littletown 873 CDP
26 Arivaca 695 CDP
27 Pimaco Two 682 CDP
28 Santa Rosa 628 CDP
29 Elephant Head 612 CDP
30 Pisinemo 321 CDP
31 Topawa 299 CDP
32 Nelson 259 CDP
33 San Miguel 197 CDP
34 Gu Oidak 188 CDP
35 Why 167 CDP
36 Ali Chuk 161 CDP
37 Maish Vaya 158 CDP
38 Anegam 151 CDP
39 Cowlic 135 CDP
40 Ali Chukson 132 CDP
41 Wahak Hotrontk 114 CDP
42 South Komelik 111 CDP
43 Rillito 97 CDP
44 Haivana Nakya 96 CDP
45 Chiawuli Tak 78 CDP
46 Ali Molina 71 CDP
47 Charco 52 CDP
48 Ventana 49 CDP
49 Ko Vaya 46 CDP
50 Summerhaven 40 CDP
51 Nolic 37 CDP
52 Ak Chin 30 CDP
53 Comobabi 8 CDP
54 Willow Canyon 1 CDP

Tourist attractions

Yearly Events

  • Pima County Fair

Locations of Interest

Recreation Attractions

See all recreational items including arts and culture, classes, community centers, outdoor activities, parks and pools, special events, stadiums and hiking/trail maps. Learn more...

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