Arizona counties by area
Official, comparable measurements for 15 counties and county equivalents.
- 1,236.3–4,496.6 mi²
- 4,621.9–5,366.7 mi²
- 5,513.8–8,122.9 mi²
- 9,188.7–9,949.5 mi²
- 11,198.4–18,616.4 mi²
- 3.7–5.8 per mi²
- 7.8–11 per mi²
- 11–20 per mi²
- 31–41 per mi²
- 101–510 per mi²
Understanding Arizona’s county areas
The land-area range runs from Santa Cruz County at 1,236.3 mi² to Coconino County at 18,616.4 mi². The largest has 15.1 times the land area of the smallest and accounts for 16.4% of the combined county land in Arizona. Compare with every state’s largest county.
The median county-equivalent land area is 6,209.9 mi², above the national median of 604.5 mi². The median describes the middle of the county size distribution; it does not describe how people or development are distributed. A state with a few very large counties can have a much smaller median than its largest entry suggests.
Where water changes the picture
Mohave County has the most assigned water area, at 128.7 mi². It also has the highest water share, with water making up 1% of its total area. Water area and water percentage answer different questions: the first measures an amount, while the second measures the mix of land and water.
Across all 15 entries, water accounts for 0.3% of the combined total area. This is calculated from the summed land and water measurements, rather than averaging county percentages, which would give each small and large county equal weight.
Where people live
An estimated 7,623,818 people lived in Arizona on July 1, 2025 (+6.5% since 2020), or 2.2% of the national total in this dataset. Maricopa County is the most populous county equivalent, with 4,689,558 residents — 61.5% of the state. The largest by land, Coconino County, has 144,368.
Across the state there are 67 people per square mile of land. County densities range from 510 in Maricopa County to 3.7 in La Paz County; the median county equivalent has 17. Switch the map above to density to see where the state’s population concentrates.
Compare the largest and smallest county equivalents in Arizona to see land, water, and total area on the same scale.
These calculations use the 2026 Census county records listed below. County-equivalent boundaries vary between states; area alone does not measure population, density, or usable land. See coverage and calculation rules.
Complete area table
Sorted from largest to smallest land area.
| # | County / equivalent | Land | Water | Water share | Population | Per mi² |
|---|---|---|---|---|---|---|
| 1 | Coconino CountyGEOID 04005 | 18,616.4 mi² | 45 mi² | 0.2% | 144,368 | 7.8 |
| 2 | Mohave CountyGEOID 04015 | 13,332.1 mi² | 128.7 mi² | 1% | 228,102 | 17 |
| 3 | Apache CountyGEOID 04001 | 11,198.4 mi² | 20.8 mi² | 0.2% | 64,445 | 5.8 |
| 4 | Navajo CountyGEOID 04017 | 9,949.5 mi² | 9.3 mi² | 0.1% | 109,946 | 11 |
| 5 | Maricopa CountyGEOID 04013 | 9,202 mi² | 23.9 mi² | 0.3% | 4,689,558 | 510 |
| 6 | Pima CountyGEOID 04019 | 9,188.7 mi² | 2 mi² | 0% | 1,074,685 | 117 |
| 7 | Yavapai CountyGEOID 04025 | 8,122.9 mi² | 4.4 mi² | 0.1% | 252,552 | 31 |
| 8 | Cochise CountyGEOID 04003 | 6,209.9 mi² | 6.8 mi² | 0.1% | 126,332 | 20 |
| 9 | Yuma CountyGEOID 04027 | 5,513.8 mi² | 5.1 mi² | 0.1% | 224,449 | 41 |
| 10 | Pinal CountyGEOID 04021 | 5,366.7 mi² | 8 mi² | 0.1% | 539,380 | 101 |
| 11 | Gila CountyGEOID 04007 | 4,757.6 mi² | 37.2 mi² | 0.8% | 53,801 | 11 |
| 12 | Graham CountyGEOID 04009 | 4,621.9 mi² | 18.3 mi² | 0.4% | 40,157 | 8.7 |
| 13 | La Paz CountyGEOID 04012 | 4,496.6 mi² | 14.1 mi² | 0.3% | 16,711 | 3.7 |
| 14 | Greenlee CountyGEOID 04011 | 1,842.8 mi² | 4.6 mi² | 0.2% | 9,312 | 5.1 |
| 15 | Santa Cruz CountyGEOID 04023 | 1,236.3 mi² | 1.2 mi² | 0.1% | 50,020 | 40 |