Overview
Maricopa County is home to 4,491,987 people (Census ACS 5-Year, 2023), making it the most populous county in Arizona and one of the largest in the United States, ranking higher than nearly all U.S. counties. The county seat is Phoenix, the state capital, and the county covers a vast stretch of central Arizona's Sonoran Desert.
The numbers paint a picture of scale. A labor force of 2,564,144 (BLS LAUS, 2025). Over 1.85 million housing units (Census ACS 5-Year, 2023). More than 2.1 million tax returns filed in a single year (IRS Statistics of Income, 2021). By virtually every volume metric, Maricopa County operates at a scale that few U.S. counties match.
Median household income sits at $85,518 (Census ACS 5-Year, 2023), higher than roughly 89% of U.S. counties. The median age is 37.5 years (Census ACS 5-Year, 2023), younger than about 82% of counties nationally. That combination of high income and relatively young population sets the economic baseline for everything else in this profile.
Demographics
At 37.5 years, Maricopa County's median age runs younger than most of the country (Census ACS 5-Year, 2023). Only about 18% of U.S. counties have a lower median age. Within Arizona, it falls roughly in the middle third of counties.
The racial and ethnic composition reflects the county's position in the Southwest. White residents make up 53.4% of the population, Hispanic residents 30.9%, Black residents 5.5%, Asian residents 4.3%, and Native American residents 1.3% (Census ACS 5-Year, 2023). The Hispanic population share is higher than about 93% of U.S. counties, consistent with the county's proximity to the U.S.-Mexico border and longstanding demographic patterns across southern Arizona.
Educational attainment is strong. About 35.9% of adults hold a bachelor's degree or higher (Census ACS 5-Year, 2023), placing the county above roughly 88% of U.S. counties. Within Arizona, only a handful of counties report higher rates. A college-educated workforce of this size feeds directly into the county's employment base and income levels.
Education
Maricopa County's public school system enrolled 735,951 students (Education Data Portal, 2021), one of the largest enrollment figures in the nation. The student-teacher ratio is 17.8:1 (Education Data Portal, 2021), above the national average of roughly 15.5:1 and higher than about 91% of U.S. counties. More students per teacher means larger class sizes on average.
Per-pupil spending was $11,501 (Education Data Portal, 2020), well below the national average of approximately $15,000. The county ranks lower than about 88% of U.S. counties on this measure. Arizona has historically ranked among the lower-spending states on K-12 education, and Maricopa County's figures reflect that pattern.
The graduation rate was 75% (Education Data Portal, 2019), below the national average of roughly 87%. That places Maricopa County lower than about 94% of counties nationally and in the bottom fifth within Arizona. The gap between the county's strong college attainment numbers and its graduation rate suggests that in-migration of college-educated workers may be doing more to lift the adult education figures than the local K-12 pipeline.
Economy & Employment
The unemployment rate in Maricopa County is 3.5% (BLS LAUS, 2025), with 88,961 residents unemployed out of a labor force of 2,564,144. That rate falls below about 61% of U.S. counties, indicating a relatively tight labor market. Within Arizona, the county's unemployment rate is among the lowest.
Median household income of $85,518 (Census ACS 5-Year, 2023) puts the county well above typical U.S. counties. Per capita income reaches $44,210 (Census ACS 5-Year, 2023), higher than about 88% of counties nationally. IRS data tells a similar story: the average adjusted gross income per return was $93,808, and average total income per return was $94,629 (IRS Statistics of Income, 2021). Total adjusted gross income across all filers exceeded $197.6 billion (IRS Statistics of Income, 2021).
The poverty rate is 11.1% (Census ACS 5-Year, 2023). That's lower than roughly 64% of U.S. counties and among the lower rates in Arizona. In a county of nearly 4.5 million people, though, 11.1% translates to a substantial number of residents living below the poverty line, close to 500,000 people.
Mean commute time is 21.2 minutes (Census ACS 5-Year, 2023), shorter than about 58% of U.S. counties. For a metro area this size, that's a relatively moderate commute. It may reflect the dispersed, car-oriented development patterns typical of Phoenix and its suburbs.
Housing & Cost of Living
The median home value in Maricopa County is $414,700 (Census ACS 5-Year, 2023), higher than about 94% of U.S. counties and among the highest in Arizona. Median gross rent is $1,587 per month (Census ACS 5-Year, 2023), above roughly 95% of counties nationally.
The county has 1,850,862 total housing units with 153,520 vacant, producing a vacancy rate of 8.3% (Census ACS 5-Year, 2023). That vacancy rate is lower than about 81% of U.S. counties and the lowest in Arizona. Low vacancy in a fast-growing county tends to push both rents and home prices upward.
Fair market rent data from HUD (2026) is available for the county but specific bedroom-level breakdowns were not provided in this dataset.
Compare the income and housing numbers side by side. A household earning the median of $85,518 faces a median home value nearly five times that income. Median rent of $1,587 per month works out to $19,044 annually, consuming about 22% of the median household's gross income. That ratio is manageable but leaves less room than it would have a decade ago, given the rapid home value appreciation across the Phoenix metro area.
Health & Wellness
Health metrics from the CDC reveal a county where several indicators fall below national norms. Obesity affects 30.6% of adults (CDC PLACES, 2023), a rate lower than roughly 93% of U.S. counties. That's a relative bright spot, though nearly a third of adults still meet the clinical threshold.
Diabetes prevalence is 9.6% (CDC PLACES, 2023), lower than about 75% of counties nationally. High blood pressure affects 28.6% of adults (CDC PLACES, 2023), a rate lower than about 89% of U.S. counties. These cardiovascular risk factors are below what most counties report.
Mental health tells a different story. About 15.3% of adults report frequent poor mental health days (CDC PLACES, 2023), higher than roughly 95% of U.S. counties. Depression affects 18.9% of adults (CDC PLACES, 2023), again higher than about 94% of counties. These are among the highest rates in the country. Within Arizona, Maricopa County reports the worst figures for both measures.
About 13.1% of adults lack health insurance (CDC PLACES, 2023), a rate higher than roughly 73% of U.S. counties. Arizona did expand Medicaid, but coverage gaps remain, particularly among the county's large working-age population.
Preventive care utilization is mixed. Cholesterol screening reaches 84.5% of adults (CDC PLACES, 2023), above about 76% of counties. But only 72% of adults had an annual checkup (CDC PLACES, 2023), lower than about 79% of U.S. counties. About 11.4% report frequent poor physical health days (CDC PLACES, 2023), higher than roughly 91% of counties nationally.
Climate & Natural Disasters
Maricopa County is one of the hottest populated places in the country. Average temperatures hit 75.1°F annually (NOAA Climate Data Online, 2025), with average highs reaching 87.4°F. That ranks in the top 1% nationally for heat. Winters are mild, with average lows of 62.3°F, but summers are genuinely extreme.
Rainfall is scarce. The county gets 10.3 inches per year (NOAA Climate Data Online, 2025), placing it in the bottom 2% nationally. Snow is effectively zero. For context, Phoenix averages more summer days above 110°F than most Americans will experience in a lifetime.
The disaster record reflects a dry, fire-prone climate. FEMA has recorded 26 disaster declarations tied to Maricopa County (FEMA OpenFEMA, 2026), with fires dominating recent history. Of the last six declarations, five were fire management events, including two in June 2024. The seasonal pattern is consistent: fires cluster in late spring and early summer, when heat peaks before the monsoon rains arrive.
Flooding is the other recurring threat. Seven flood declarations appear in the record going back to 1966. That may seem counterintuitive for a desert county, but the combination of hardpan soil, steep terrain, and intense monsoon downpours makes flash flooding a real and recurring risk. The county's most recent flood declaration came in 2014 (FEMA OpenFEMA, 2026).
The national ranking on disaster count (higher than 76% of U.S. counties) reflects both the county's size and its climate vulnerabilities. As the county continues to grow and summers trend hotter, both wildfire exposure and extreme heat risk are likely to intensify.
Financial Profile
Maricopa County filed 2,106,950 tax returns in 2021 (IRS Statistics of Income), more than any other county in the country. Total adjusted gross income reached $197.6 billion that year, also first nationally. The scale reflects population, not extraordinary wealth: average AGI was $93,808 per return, higher than about 92% of U.S. counties. That's comfortably above the national middle, but it's not in the same territory as smaller, wealthier counties in the Northeast or Silicon Valley.
The county holds $53.4 billion in total deposits across 65 bank branches (FDIC, 2023). Both figures rank in the top 10% nationally, with total deposits higher than about 98% of U.S. counties. That high deposit-per-branch concentration is consistent with a metro where large regional institutions do most of the business.
Social Security beneficiaries number 791,725 (SSA, 2024), more than any county in the nation. Maricopa's retirement draw is well-documented, and the OASDI figures confirm the scale of it. A county this size with this much fixed retirement income has built-in demand stability, though it also means a substantial share of household income isn't tied to the local labor market.
The aggregate financial picture is enormous. The per-household picture is solid but not exceptional. As the county keeps growing, those two facts are likely to stay true together.
Key Comparisons
Maricopa County's scale sets it apart from most comparison points. With a population higher than all but a handful of U.S. counties, straight comparisons with "the typical county" can be misleading. Still, the data reveals clear patterns.
Income runs well above average. Median household income of $85,518 (Census ACS 5-Year, 2023) exceeds about 89% of U.S. counties and ranks near the top in Arizona. Per capita income follows the same pattern at $44,210 (Census ACS 5-Year, 2023).
Housing costs track with those higher incomes. The median home value of $414,700 (Census ACS 5-Year, 2023) is higher than about 94% of U.S. counties, and the median rent of $1,587 (Census ACS 5-Year, 2023) exceeds 95%.
Education spending works in the opposite direction. Per-pupil spending of $11,501 (Education Data Portal, 2020) falls below the national average by roughly $3,500. The 75% graduation rate (Education Data Portal, 2019) is well below the 87% national average.
Health outcomes split. Physical health indicators like obesity (30.6%), diabetes (9.6%), and high blood pressure (28.6%) all come in below most U.S. counties (CDC PLACES, 2023). Mental health indicators go the other direction, with depression at 18.9% and poor mental health days at 15.3%, both among the highest rates nationally (CDC PLACES, 2023).
The county's young median age of 37.5 years (Census ACS 5-Year, 2023) and low unemployment rate of 3.5% (BLS LAUS, 2025) point to an active, working-age population base. Combined with the high uninsured rate of 13.1% (CDC PLACES, 2023), this suggests that access to care, not just health status, remains a gap worth watching, particularly as the population continues to grow.
Data Sources
- Census ACS 5-Year, 2023: Population, income, housing, demographics, education attainment, commute times, poverty rate
- BLS LAUS, 2025: Unemployment rate, labor force, employment counts
- CDC PLACES, 2023: Health metrics including obesity, diabetes, mental health, insurance coverage, preventive care
- HUD Fair Market Rents, 2026: Fair market rent by bedroom count
- FEMA OpenFEMA, 2026: Disaster declarations and history
- IRS Statistics of Income, 2021: Tax returns, adjusted gross income, total income
- FDIC Summary of Deposits, 2023: Bank branch counts and total deposits
- NOAA Climate Data Online, 2025: Temperature and precipitation averages
- SSA OASDI, 2024: Social Security beneficiary counts
- USDA Census of Agriculture, 2022: Data not available for Maricopa County
- Education Data Portal, 2021: Per-pupil spending, enrollment, student-teacher ratio, graduation rate