County outline
Where Maricopa County is located
Area breakdown
Land accounts for 99.7% of Maricopa County’s measured area and water for 0.3%. Its combined area converts to 23,895.2 square kilometers or approximately 5,904,628 acres.
Green: land · blue: water
| Measurement | Square miles | Square kilometers | Acres |
|---|---|---|---|
| Land | 9,202.04 | 23,833.174 | 5,889,305.6 |
| Water | 23.941 | 62.007 | 15,322.2 |
| Total | 9,225.981 | 23,895.181 | 5,904,627.8 |
How Maricopa County compares
By original Census land area, Maricopa County ranks #5 of 15 in Arizona and #28 of 3,222 nationally. National rankings include the 50 states, District of Columbia, and Puerto Rico.
Its land area is 1.482 times the Arizona county-equivalent median of 6,209.9 square miles. It accounts for 8.1% of the combined county land area in the state.
See the complete Arizona ranking · What counts as a county equivalent?
Population and density of Maricopa County
The Census Bureau estimates that 4,689,558 people lived in Maricopa County on July 1, 2025. That ranks #4 of 3,222 county equivalents nationally and #1 of 15 in Arizona. Since the April 1, 2020 estimates base of 4,425,302, the population has grown by 264,256 (+6%), compared with +6.5% for Arizona as a whole.
With 9,202 square miles of land, that is 510 people per square mile (197 per km²), placing Maricopa County #335 nationally for density and #1 in Arizona. The median county equivalent has 47 people per square mile; the Arizona median is 17. Put another way, there are about 1.3 acres of land per resident.
| July 1 | 2020 | 2021 | 2022 | 2023 | 2024 | 2025 |
|---|---|---|---|---|---|---|
| Estimate | 4,445,025 | 4,500,059 | 4,559,561 | 4,601,077 | 4,654,147 | 4,689,558 |
| Change | — | +55,034 | +59,502 | +41,516 | +53,070 | +35,411 |
U.S. Census Bureau, Vintage 2025 population estimates. Estimates are revised each year and are not decennial census counts. Density divides the whole population by the whole county’s land area, so it describes an average, not how settlement is distributed within the county. Population sources and methods.
Cities and towns in Maricopa County
25 incorporated places lie at least partly in Maricopa County. Together they are home to 4,359,239 people (93%); the other 330,319 (7%) live outside any incorporated place, in unincorporated communities and rural areas.
The largest is Phoenix city, with 1,665,481 residents in the county. Among places with at least 1,000 residents in 2020, Queen Creek town grew fastest since then (+48.6%).
| Incorporated place | Population 2025 | Since 2020 | Land mi² |
|---|---|---|---|
| Phoenix cityCounty seat | 1,665,481 | +3.6% | 518.5 |
| Mesa city | 513,656 | +1.8% | 142.1 |
| Gilbert town | 287,285 | +7.2% | 68.8 |
| Chandler city | 278,748 | +1% | 65.7 |
| Glendale city | 260,572 | +4.9% | 67.3 |
| Scottsdale city | 243,006 | +0.7% | 184 |
| Peoria cityAlso in 1 other county | 200,881 | +5.2% | 177.4 |
| Tempe city | 190,571 | +3.5% | 40 |
| Surprise city | 175,304 | +22.5% | 110.5 |
| Buckeye city | 125,445 | +37.1% | 396.1 |
| Goodyear city | 125,359 | +30.4% | 191.3 |
| Avondale city | 100,983 | +13.1% | 47.8 |
| Queen Creek townAlso in 1 other county | 74,563 | +48.6% | 42.1 |
| El Mirage city | 35,820 | +0.1% | 9.915 |
| Fountain Hills town | 23,625 | −0.8% | 20.3 |
Show the other 10 places
| Name | Population 2025 | Since 2020 | Land mi² |
|---|---|---|---|
| Paradise Valley town | 12,251 | −3.2% | 15.4 |
| Tolleson city | 9,224 | +27.8% | 5.733 |
| Youngtown town | 7,039 | −0.3% | 1.487 |
| Litchfield Park city | 6,727 | −1.8% | 3.313 |
| Wickenburg townAlso in 1 other county | 6,647 | −0.6% | 27 |
| Cave Creek town | 5,160 | +5.5% | 37.7 |
| Guadalupe town | 5,093 | −4.2% | 0.799 |
| Carefree town | 3,600 | −2.2% | 8.809 |
| Gila Bend town | 1,816 | −3.9% | 64.4 |
| Apache Junction cityAlso in 1 other county | 383 | −1.8% | 45.5 |
Population: U.S. Census Bureau Vintage 2025 subcounty estimates, counting only the part of each place inside Maricopa County. Land: 2026 Census Gazetteer, for the whole place even where it extends into other counties. How communities are listed.
Metropolitan area
Maricopa County is a central county of the Phoenix-Mesa-Chandler, AZ Metropolitan Statistical Area. Its 2 county equivalents have 5,228,938 residents on 14,568.7 square miles of land; Maricopa County accounts for 63.2% of the land and 89.7% of the residents. By combined land it ranks #4 of 393 metropolitan areas, and #10 by population. It belongs to the Phoenix-Mesa, AZ Combined Statistical Area.
| County equivalent | Population 2025 | Land mi² |
|---|---|---|
| Maricopa County | 4,689,558 | 9,202 |
| Pinal County | 539,380 | 5,366.7 |
ZIP codes
140 ZIP Code Tabulation Areas have land in Maricopa County; 135 of them have most of their land inside the county, and the others mainly cover neighboring areas.
8500385004850068500785008850098501285013850148501585016850178501885019850208502185022850238502485026850278502885029850318503285033850348503585037850408504185042850438504485045850488505085051850538505485083850858508685087851208513985142852018520285203852048520585206852078520885209852108521285213852158522485225852268523385234852368524885249852508525185253852548525585256852578525885259852608526285263852648526685268852818528285283852848528685295852968529785298853018530285303853048530585306853078530885309853108532085321853228532385326853298533185333853358533785338853398534085342853438534585351853538535485355853618536385373853748537585377853788537985381853828538385387853888539085392853958539685545
ZIP Code Tabulation Areas are the Census Bureau’s approximations of USPS ZIP Code service areas, from the 2020 Census relationship files. Lighter codes have less than half of their land in this county. Post-office-box and single-address ZIP Codes have no tabulation area.
Counties bordering Maricopa County
Maricopa County shares a land border with 6 county equivalents. It has more land than every one of them. The largest neighbor is Pima County (9,188.7 mi²) and the smallest is La Paz County (4,496.6 mi²). Together with its neighbors, Maricopa County forms a block of 46,648.3 mi² of land, of which it holds 19.7%.
| Bordering county equivalent | Land mi² | Size vs. Maricopa | Compare |
|---|---|---|---|
| Pima County | 9,188.7 | about the same | Compare |
| Yavapai County | 8,122.9 | 1.1× smaller | Compare |
| Yuma County | 5,513.8 | 1.7× smaller | Compare |
| Pinal County | 5,366.7 | 1.7× smaller | Compare |
| Gila County | 4,757.6 | 1.9× smaller | Compare |
| La Paz County | 4,496.6 | 2× smaller | Compare |
How big is Maricopa County compared with U.S. states?
Maricopa County has more land than 7 of the 50 states. It is about 1 times the land area of New Hampshire (8,954 mi²), while Vermont, the next larger state, has 1 times as much land (9,217.3 mi²). Arizona’s county land could hold about 12 areas the size of Maricopa County.
Another way to picture it: the same land area would fill a square about 95.9 miles (154.4 km) on each side. Real county shapes are rarely square, so this is a scale reference rather than a width or driving distance.
State figures are the sums of each state’s county-equivalent land measurements in the same Census release, so states and counties are compared on the same basis. Published state totals can differ slightly because of rounding. Compare all states · Counties bigger than entire states.
What stands out about Maricopa County?
Maricopa County has more land than 3,194 of the other 3,221 county equivalents in the dataset.
A median is the middle county-equivalent measurement, not the average of the largest and smallest. All three bars use the same linear scale. Very small areas may appear as a thin sliver; the labels retain their values.
Does including water change its rank?
Using land plus water places Maricopa County at #34 nationally by total area, 6 places farther from the top than its land rank. Other county equivalents gain more area when their water measurements are included.
Its water share is 0.3%, compared with a national county-equivalent median of 1.2% — 0.9 percentage points lower. This describes the statistical geography’s land/water mix, not flood exposure or developable land.
Closest positions in the national land ranking
These entries sit immediately beside Maricopa County in the national ranking. They can be in different states and are not necessarily geographic neighbors.
| Land rank | County equivalent | Land mi² | Comparison |
|---|---|---|---|
| #27 | Chugach Census Area, Alaska | 9,574.5 | Compare |
| #28 | Maricopa County, Arizona | 9,202 | This county |
| #29 | Pima County, Arizona | 9,188.7 | Compare |
Calculated from the same Census release as the area table. Total-area order uses original ALAND + AWATER; water shares and chart labels use published square miles. Calculation details.
Representative coordinates
The Census internal point is 33.345176, -112.498930. It represents a location inside the geography; it is not necessarily the centroid or the address of a courthouse.
Source and precision
U.S. Census Bureau, 2026 Gazetteer Files, Counties. Original ALAND: 23,833,172,607 m²; AWATER: 62,006,320 m². Rankings use ALAND; exact ties use ascending GEOID. Tables preserve Census-published square miles to three decimals, with conversions based on those values.
Common questions
How big is Maricopa County?
Maricopa County, Arizona has 9,202 square miles (23,833.2 km²) of land and 23.9 square miles of water, for a total area of 9,226 square miles. It ranks #28 of 3,222 U.S. county equivalents by land area.
Is Maricopa County the largest county in Arizona?
No. Maricopa County ranks #5 of 15 in Arizona by land area. The largest is Coconino County, with 18,616.4 square miles of land.
What counties border Maricopa County?
Maricopa County shares a land border with Pinal County, Yavapai County, Pima County, Yuma County, Gila County, and La Paz County.
What is the population of Maricopa County?
The Census Bureau estimates Maricopa County had 4,689,558 residents on July 1, 2025, ranking #4 of 3,222 county equivalents. That is 510 people per square mile of land.
What is the county seat of Maricopa County?
The county seat of Maricopa County is Phoenix.
What cities and towns are in Maricopa County?
Maricopa County has 25 incorporated places. The most populous five are Phoenix city, Mesa city, Gilbert town, Chandler city, and Glendale city; 330,319 residents live outside any incorporated place.
Is Maricopa County part of a metropolitan area?
Yes. It is a central county of the Phoenix-Mesa-Chandler, AZ Metropolitan Statistical Area, which has 2 county equivalents and 5,228,938 residents.
How many ZIP codes are in Maricopa County?
140 ZIP Code Tabulation Areas have land in Maricopa County, and 135 of them have most of their land inside the county. Census ZIP Code Tabulation Areas approximate USPS ZIP Code areas.
How does Maricopa County compare with U.S. states?
It has more land than 7 of the 50 states, including New Hampshire (8,954 square miles of land).
How many acres of land are in Maricopa County?
The land measurement converts to approximately 5,889,306 acres. Including water, total area is approximately 5,904,628 acres. One square mile equals 640 acres.
Why might another source show a different area?
Check whether it reports land or total area, its Census vintage, and its rounding. Our guide explains how to reconcile county area figures.
Can this establish a property boundary?
No. Statistical measurements and generalized maps do not establish property lines. Consult the relevant local surveying or land-records authority.