Maricopa County vs Pima County
Two neighbouring counties in Arizona, compared on population, size, income and housing. They share 66 mi of border.
Maricopa County
Arizona
Pima County
Arizona
Both outlines are drawn at true relative size. Pima County spans about 275.2 km at its widest.
Side by side
| Measure | Maricopa County | Difference | Pima County |
|---|---|---|---|
| Population | 4,689,558 | +336.4% | 1,074,685 |
| Change since 2020 | 5.5% | +2.7 pp | 2.8% |
| Land area | 9,202 sq mi | +0.1% | 9,189 sq mi |
| Population density | 510 per sq mi | +335.9% | 117 per sq mi |
| Median household income | $89,300 | +27.0% | $70,315 |
| Median home value | $452,800 | +41.6% | $319,700 |
| Median age | 37.6 | -5.5% | 39.8 |
| Households | 1,730,696 | +295.3% | 437,827 |
| Housing units | 1,884,334 | +292.6% | 479,939 |
Sources: US Census Bureau, Population Estimates Program, Vintage 2025 Population Estimates, released 26 March 2026; US Census Bureau, Gazetteer Files, 2025 Gazetteer Files, released 10 September 2025; US Census Bureau, American Community Survey, American Community Survey 2020-2024 5-Year Estimates, released 29 January 2026; US Census Bureau, County Adjacency File, 2025 County Adjacency File, released 15 September 2025. The difference column is computed here: the first county's figure against the second, expressed as a percentage of the second. The change-since-2020 row is the exception: two growth rates differ in percentage points (pp), not percent. Retrieved 30 August 2026.
What the numbers say
- Maricopa County holds about 4.4 times the population of Pima County: 4,689,558 against 1,074,685.
- Maricopa County covers more ground, at 9,202 square miles against 9,189.
- Maricopa County is the more crowded of the two, at 510 people per square mile against 117.
- Median household income is higher in Maricopa County, by 18,985 dollars a year.
- Since 2020, Maricopa County has grown by 5.5% and Pima County has grown by 2.8%.
- They share 66 mi of common border, which the Census Bureau publishes in its county adjacency file and which almost no other county reference presents.
Full pages
Want a different pair? Compare any two of the 3,144 US counties.
Rebuilt from source data 30 August 2026. How these figures are produced.