Maricopa County, Arizona

Adjacent counties

• La Paz County – west
• Yuma County – west
• Pima County – south
• Pinal County – southeast and south
• Gila County – east
• Yavapai County – north

National protected areas

• Sonoran Desert National Monument (part)
• Tonto National Forest (part)

Regional parks

Maricopa County has 14 regional parks:

• Adobe Mountain Desert Park
• Chaparral Lake
• Estrella Mountain Regional Park
• Hassayampa River Preserve
• Indian Mesa
• Lake Pleasant Regional Park
• Litchfield Park, Arizona
• Manistee Ranch
• McCormick-Stillman Railroad Park
• Papago Park
• Phoenix Mountains Preserve
• Sahuaro Ranch
• San Tan Mountain Regional Park
• White Tank Mountain Regional Park.

It also has at least 21 protected areas:

• Big Horn Mountains Wilderness
• Daisy Mountain Preserve
• Deer Valley Petroglyph Preserve
• Eagletail Mountains Wilderness
• Harquahala Mountains
• Hells Canyon Wilderness (Arizona)
• Hummingbird Springs Wilderness
• Mesa Grande
• Mummy Mountain (Arizona)
• National Memorial Cemetery of Arizona
• Painted Rock Petroglyph Site
• Sierra Estrella
• Signal Mountain Wilderness
• Sonoran Desert National Monument
• St. Francis Catholic Cemetery
• Superstition Mountains
• Table Top Mountain (Arizona)
• Tonto National Forest
• Wabayuma Peak
• White Tank Mountain Regional Park
• Woolsey Peak

Flora and fauna

From 2009 to 2011, an inventory of all vascular plants growing along the Salt River (Arizona), Gila River, New River and Agua Fria River and their tributaries in the Phoenix metropolitan area was done.^[7] In October 2022, Maricopa County Environmental Services Department detected Dengue virus in mosquitoes they had trapped; in November the first locally transmitted case of dengue fever was reported in the County and Arizona state as a whole - previous dengue cases in Maricopa County had been related to travel.^[8]

Racial and ethnic composition since 1960

2020 census

As of the 2020 census, the county had a population of 4,420,568. Of the residents, 23.5% were under the age of 18 and 16.1% were 65 years of age or older; the median age was 37.2 years. For every 100 females there were 97.1 males, and for every 100 females age 18 and over there were 94.9 males. 97.7% of residents lived in urban areas and 2.3% lived in rural areas.^[18][19]

The racial makeup of the county was 59.8% White, 5.9% Black or African American, 2.3% American Indian and Alaska Native, 4.6% Asian, 0.2% Native Hawaiian and Pacific Islander, 13.5% from some other race, and 13.6% from two or more races. Hispanic or Latino residents of any race comprised 30.6% of the population.^[20]

There were 1,643,579 households in the county, of which 31.5% had children under the age of 18 living with them and 26.2% had a female householder with no spouse or partner present. About 25.5% of all households were made up of individuals and 9.8% had someone living alone who was 65 years of age or older.^[18]

There were 1,812,827 housing units, of which 9.3% were vacant. Among occupied housing units, 63.0% were owner-occupied and 37.0% were renter-occupied. The homeowner vacancy rate was 1.6% and the rental vacancy rate was 8.4%.^[18]

2010 census

As of the 2010 census, 3,817,117 people, 1,411,583 households, and 932,814 families were living in the county.^[24] The population density was 414.9/sq mi (160.2/km²). The 1,639,279 housing units averaged 178.2/sq mi (68.8/km²).^[25] The racial makeup of the county was 73.0% white (58.7% non-Hispanic white), 5.0% African American, 3.5% Asian, 2.1% American Indian, 0.2% Pacific islander, 12.8% from other races, and 3.5% from two or more races. Those of Hispanic or Latino origin made up 29.6% of the population.^[24] The largest ancestry groups were:^[26]

Of the 1,411,583 households, 35.1% had children under 18 living with them, 47.8% were married couples living together, 12.4% had a female householder with no husband present, 33.9% were not families, and 25.9% of all households were made up of individuals. The average household size was 2.67 and the average family size was 3.25. The median age was 34.6 years.^[24]

The median income for a household in the county was $55,054 and the median income for a family was $65,438. Males had a median income of $45,799 versus $37,601 for females. The per capita income for the county was $27,816. About 10.0% of families and 13.9% of the population were below the poverty line, including 19.8% of those under age 18 and 7.0% of those age 65 or over.^[27]

According to data provided by the United States Census Bureau in October 2015 and collected from 2009 to 2013, 73.7% of the population aged five years and over spoke only English at home, while 20.3% spoke Spanish, 0.6% spoke Chinese, 0.5% Vietnamese, 0.4% Tagalog, 0.4% Arabic, 0.4% German, 0.3% French, 0.3% Navajo, 0.2% Korean, 0.2% Hindi, 0.2% Italian, 0.1% Persian, 0.1% Russian, 0.1% Serbo-Croatian, 0.1% Telugu, 0.1% Polish, 0.1% Syriac, 0.1% Japanese, 0.1% spoke Romanian, and 0.1% spoke other Native North American languages at home.^[28]

2000 census

As of the census of 2000, 3,072,149 people, 1,132,886 households, and 763,565 families were living in the county. The population density was 334 people/mi² (129 people/km²). The 1,250,231 housing units averaged of 136 per square mile (53/km²). The racial makeup of the county was 77.4% White, 3.7% African American, 1.9% Native American, 2.2% Asian, 12.0% from other races, and 2.9% from two or more races. About 29.5% of the population were Hispanics or Latinos of any race. About 19.1% reported speaking Spanish at home.^[29]

Of the 1,132,886 households, 33.0% had children under 18 living with them, 51.6% were married couples living together, 10.7% had a female householder with no husband present, and 32.6% were not families. About 24.5% of all households were made up of individuals, and 7.9% had someone living alone who was 65 or older. The average household size was 2.67, and the average family size was 3.21.

The age distribution in the county was 27.0% under 18, 10.2% from 18 to 24, 31.4% from 25 to 44, 19.8% from 45 to 64, and 11.7% who were 65 or older. The median age was 33 years. For every 100 females, there were 100.10 males. For every 100 females age 18 and over, there were 98.10 males.

The median income for a household in the county was $45,358, and for a family was $51,827. Males had a median income of $36,858 versus $28,703 for females. The per capita income for the county was $22,251. About 8.0% of families and 11.7% of the population were below the poverty line, including 15.4% of those under age 18 and 7.4% of those age 65 or over.

Religion

In 2010 statistics, the largest religious group in Maricopa County were Catholics, who are organized under the Roman Catholic Diocese of Phoenix with 519,950 Catholics and 99 parishes, and 9 additional eastern rite Catholic parishes. This is followed by 242,732 LDS Mormons with 503 congregations, 213,640 non-denominational adherents with 309 congregations, 93,252 Assembly of God Pentecostals with 120 congregations, 73,207 Southern Baptists with 149 congregations, 35,804 Christian churches and churches of Christ Christians with 29 congregations, 30,014 Evangelical Lutherans with 47 congregations, 28,634 UMC Methodists with 55 congregations, 18,408 Missouri Synod Lutherans with 34 congregations, and 15,001 Presbyterians with 42 congregations. Altogether, 39.1% of the population was claimed as members by religious congregations, although members of historically African-American denominations were underrepresented due to incomplete information.^[30] In 2014, the county had 1,177 religious organizations, the fifth most out of all US counties.^[31]

Government

The governing body of Maricopa County is its board of supervisors. The Maricopa County Board of Supervisors consists of five members chosen by popular vote within their own districts. As of 2025^[update] the board consists of four Republicans and one Democrat. Each member serves a four-year term, with no term limits.

Maricopa County Sheriff

The Maricopa County Sheriff's Office provides court protection, administers the county jail, and patrols the unincorporated areas of the county plus incorporated towns by contract.

Politics

For much of the time after World War II, Maricopa County was one of the more conservative urban counties in the United States. While the city of Phoenix has historically leaned Republican, most of the rest of the county was more conservative. Until 2020, every Republican presidential candidate since 1952 had carried Maricopa County. This includes the 1964 presidential run of native son Barry Goldwater, who would not have carried his own state had it not been for a 21,000-vote margin in Maricopa County. Until 2020, it was the largest county in the country to vote Republican. From 1968 to 2016, Democrats held the margin within single digits only three times–in 1992, 1996, and 2016. In 2020, Joe Biden became the first Democrat in 72 years to win the county, which flipped Arizona to the Democratic column for the first time since 1996 and only the second time since 1948.^[32] Furthermore, Biden became the first presidential candidate to win more than one million votes in the county. This makes Maricopa County the third county in American history to cast more than one million votes for a presidential candidate. The county is also a statewide bellwether, voting for the statewide winning candidate in all elections except 1996. In 2024, however, Donald Trump was able to flip the county back as he carried Arizona in that election due to his increase in support among Hispanics in Phoenix and its suburbs.

Despite its consistent Republican allegiance since 1952, its fast-growing Hispanic population and influx of conservative retirees and Mormons, which were traditionally conservative voting blocs but were increasingly skeptical of President Donald Trump, signaled that it was a crucial bellwether in the 2020 election.^[33]

Despite its political leanings at the time, Maricopa County voted against Proposition 107 in the 2006 election. This referendum, designed to ban gay marriage and restrict domestic partner benefits, was rejected by a 51.6–48.4% margin within the county, and statewide by a similar margin. Two years later, however, a majority of county residents voted to pass a more limited constitutional amendment Proposition 102 to ban same-sex marriage but not state-recognized civil unions or domestic partnerships. The amendment was later invalidated by the Supreme Court's 2015 ruling in Obergefell v. Hodges, which declared that same-sex marriage is a fundamental right in the United States.

Unlike cities and towns in Arizona, counties are politically and legally subordinate to the state and do not have charters of their own. The county Board of Supervisors acts under powers delegated by state law, mainly related to minor ordinances and revenue collection. With few exceptions, these powers are narrowly construed. The chairperson of the board presides for a one-year term, selected by the board members during a public hearing.

The county sheriff, county attorney, county assessor, county treasurer, superintendent of schools, county recorder, constables, justices of the peace, and clerk of the Superior Court are elected by the people. Retention of Superior Court judges is also determined by popular vote.

The county's dominant political figure for over two decades (from 1993 to 2017) was Sheriff Joe Arpaio, who called himself "America's Toughest Sheriff" and gained national notoriety for his flamboyant and often controversial practices and policies.^[38]

Maricopa County is home to 62 percent of the state's population and therefore dominates Arizona's politics. For example, in the 2018 Senate election, Democrat Kyrsten Sinema carried the county en route to becoming the first Democrat to win a Senate seat in Arizona since 1988.^[39] She won the county by over 60,000 votes, more than enough for the victory; she won statewide by 55,900 votes.^[40] All but one of the state's nine congressional districts include part of the county, and five of the districts have their population center located there. Most of the state's prominent elected officials live in the county. Further underlining Maricopa County's political dominance, Biden's margin of 45,109 votes was more than enough to carry the state; he only won Arizona by 10,457 votes.

Conversely, in the 2024 General Election, former president Donald Trump won Maricopa County by 71,515 votes and won the state of Arizona by 187,382 votes, making the 5.5 percent statewide victory the largest percentage win of any of the seven 2024 swing states.^[41]

Elected officials

K-12 schools

School districts with territory in the county (no matter how slight, even if the administration and schools are in other counties) include:^[47]

Unified:

Secondary:

Elementary:

There is also a state-operated school, Phoenix Day School for the Deaf.

The Phoenix Indian School was formerly in the county.

Major highways

Air

The major primary commercial airport of the county is Phoenix Sky Harbor International Airport (PHX).

Other airports located in the county include:

• Phoenix-Mesa Gateway Airport in Mesa (AZA)
• Scottsdale Municipal Airport in Scottsdale (SCF)
• Deer Valley Airport in Deer Valley Village in Phoenix (DVT)
• Chandler Municipal Airport in Chandler (CHD)
• Phoenix Goodyear Airport in Goodyear (GYR)
• Glendale Municipal Airport in Glendale (GEU)
• Buckeye Municipal Airport in Buckeye (BXK)
• Falcon Field in Mesa (MSC)
• Gila Bend Municipal Airport in Gila Bend (E63)
• Wickenburg Municipal Airport in Wickenburg (E25)

Rail

In terms of freight rail, the Union Pacific Railroad and the Burlington Northern Santa Fe Railroad serve the county.

In terms of passenger rail, greater Phoenix is served by a light rail system. The county has no other passenger rail transport as Amtrak's Sunset Limited, which served Phoenix until June 2, 1996, has its closest stop in Maricopa in neighboring Pinal County. The train connects Maricopa to Tucson, Los Angeles, and New Orleans three times a week. However, it does not stop in Phoenix itself.

Cities

Towns

Census-designated places

Unincorporated communities

Ghost towns

Native American communities

• Fort McDowell Yavapai Nation
• Gila River Indian Community
• Salt River Pima–Maricopa Indian Community
• Tohono O'odham Indian Reservation

County population ranking

The population ranking of the following table is based on the 2020 census of Maricopa County.^[48][49]

† county seat