Utah counties by area
Official, comparable measurements for 29 counties and county equivalents.
- 324.9–758.2 mi²
- 1,028.8–1,870.7 mi²
- 1,910.5–3,235.5 mi²
- 3,296.2–4,482.9 mi²
- 5,179.6–7,823.7 mi²
- 1–2.1 per mi²
- 2.2–4 per mi²
- 6.4–14 per mi²
- 20–88 per mi²
- 124–1,622 per mi²
Understanding Utah’s county areas
The land-area range runs from Davis County at 324.9 mi² to San Juan County at 7,823.7 mi². The largest has 24.1 times the land area of the smallest and accounts for 9.5% of the combined county land in Utah. Compare with every state’s largest county.
The median county-equivalent land area is 2,427.6 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
Box Elder County has the most assigned water area, at 947.9 mi². Davis County has the highest water share, with water making up 48.9% 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 29 entries, water accounts for 2.7% 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 3,538,904 people lived in Utah on July 1, 2025 (+8.2% since 2020), or 1% of the national total in this dataset. Salt Lake County is the most populous county equivalent, with 1,220,916 residents — 34.5% of the state. The largest by land, San Juan County, has 14,542.
Across the state there are 43 people per square mile of land. County densities range from 1,622 in Salt Lake County to 1 in Garfield County; the median county equivalent has 11. Switch the map above to density to see where the state’s population concentrates.
Compare the largest and smallest county equivalents in Utah 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 | San Juan CountyGEOID 49037 | 7,823.7 mi² | 110.1 mi² | 1.4% | 14,542 | 1.9 |
| 2 | Tooele CountyGEOID 49045 | 7,040.3 mi² | 245.7 mi² | 3.4% | 87,461 | 12 |
| 3 | Millard CountyGEOID 49027 | 6,785.5 mi² | 51.5 mi² | 0.8% | 14,057 | 2.1 |
| 4 | Box Elder CountyGEOID 49003 | 5,781.3 mi² | 947.9 mi² | 14.1% | 65,320 | 11 |
| 5 | Garfield CountyGEOID 49017 | 5,179.6 mi² | 29.3 mi² | 0.6% | 5,256 | 1 |
| 6 | Uintah CountyGEOID 49047 | 4,482.9 mi² | 21.6 mi² | 0.5% | 38,278 | 8.5 |
| 7 | Emery CountyGEOID 49015 | 4,462.6 mi² | 9.5 mi² | 0.2% | 10,177 | 2.3 |
| 8 | Kane CountyGEOID 49025 | 3,994.1 mi² | 113.1 mi² | 2.8% | 8,597 | 2.2 |
| 9 | Grand CountyGEOID 49019 | 3,672.9 mi² | 11.8 mi² | 0.3% | 9,790 | 2.7 |
| 10 | Juab CountyGEOID 49023 | 3,391.8 mi² | 14 mi² | 0.4% | 13,567 | 4 |
| 11 | Iron CountyGEOID 49021 | 3,296.2 mi² | 4.4 mi² | 0.1% | 67,141 | 20 |
| 12 | Duchesne CountyGEOID 49013 | 3,235.5 mi² | 15 mi² | 0.5% | 20,856 | 6.4 |
| 13 | Beaver CountyGEOID 49001 | 2,582.9 mi² | 2 mi² | 0.1% | 7,301 | 2.8 |
| 14 | Wayne CountyGEOID 49055 | 2,461.1 mi² | 5.7 mi² | 0.2% | 2,587 | 1.1 |
| 15 | Washington CountyGEOID 49053 | 2,427.6 mi² | 3 mi² | 0.1% | 213,670 | 88 |
| 16 | Utah CountyGEOID 49049 | 2,004.5 mi² | 139.8 mi² | 6.5% | 759,859 | 379 |
| 17 | Sevier CountyGEOID 49041 | 1,910.5 mi² | 7.8 mi² | 0.4% | 22,827 | 12 |
| 18 | Summit CountyGEOID 49043 | 1,870.7 mi² | 10 mi² | 0.5% | 43,141 | 23 |
| 19 | Sanpete CountyGEOID 49039 | 1,589.8 mi² | 12.4 mi² | 0.8% | 31,453 | 20 |
| 20 | Carbon CountyGEOID 49007 | 1,479.3 mi² | 6 mi² | 0.4% | 20,680 | 14 |
| 21 | Wasatch CountyGEOID 49051 | 1,177 mi² | 30.5 mi² | 2.5% | 38,514 | 33 |
| 22 | Cache CountyGEOID 49005 | 1,164.7 mi² | 8.2 mi² | 0.7% | 145,000 | 124 |
| 23 | Rich CountyGEOID 49033 | 1,028.8 mi² | 57.6 mi² | 5.3% | 2,687 | 2.6 |
| 24 | Piute CountyGEOID 49031 | 758.2 mi² | 7.8 mi² | 1% | 1,509 | 2 |
| 25 | Salt Lake CountyGEOID 49035 | 752.7 mi² | 52.8 mi² | 6.6% | 1,220,916 | 1,622 |
| 26 | Daggett CountyGEOID 49009 | 696.5 mi² | 23.6 mi² | 3.3% | 934 | 1.3 |
| 27 | Weber CountyGEOID 49057 | 611 mi² | 48.9 mi² | 7.4% | 278,174 | 455 |
| 28 | Morgan CountyGEOID 49029 | 609.2 mi² | 1.7 mi² | 0.3% | 13,383 | 22 |
| 29 | Davis CountyGEOID 49011 | 324.9 mi² | 310.5 mi² | 48.9% | 381,227 | 1,173 |