County facts · United States · October 22, 2026
Most Densely Populated Counties in the US
The 20 most and 10 least densely populated US counties, from 2023 Census estimates and 2020 land area, with each official parcel map.
Looking for the most densely populated counties in the US? New York County, NY leads by far, with about 70,509 people per square mile of land, using the Census Bureau's July 1, 2023 estimate and its 2020 Gazetteer land area. At the other end, Yukon-Koyukuk Census Area, AK has about 0.04 people per square mile.
Across the country the median county has about 45 people per square mile.
The 20 most densely populated US counties
| # | County or equivalent | State | People per sq mi | 2023 pop. | Land (sq mi) | Parcel viewer |
|---|---|---|---|---|---|---|
| 1 | New York County | New York | 70,509 | 1,597,451 | 23 | county web map |
| 2 | Kings County | New York | 36,917 | 2,561,225 | 69 | county web map |
| 3 | Bronx County | New York | 32,165 | 1,356,476 | 42 | county web map |
| 4 | Queens County | New York | 20,715 | 2,252,196 | 109 | county web map |
| 5 | San Francisco County | California | 17,244 | 808,988 | 47 | county web map |
| 6 | Hudson County | New Jersey | 15,272 | 705,472 | 46 | county web map |
| 7 | Suffolk County | Massachusetts | 13,191 | 768,425 | 58 | MassGIS Interactive Property Map |
| 8 | Philadelphia County | Pennsylvania | 11,541 | 1,550,542 | 134 | county web map |
| 9 | District of Columbia | District of Columbia | 11,108 | 678,972 | 61 | county web map |
| 10 | City of Alexandria | Virginia | 10,394 | 155,230 | 15 | county web map |
| 11 | Arlington County | Virginia | 9,007 | 234,162 | 26 | county web map |
| 12 | Richmond County | New York | 8,530 | 490,687 | 58 | county web map |
| 13 | City of Falls Church | Virginia | 7,177 | 14,685 | 2.0 | VGIN Virginia Parcels map (Service View) |
| 14 | Baltimore City | Maryland | 6,983 | 565,239 | 81 | Maryland FINDER Online (MD Dept. of Planning) |
| 15 | Essex County | New Jersey | 6,750 | 851,117 | 126 | ArcGIS Map Viewer |
| 16 | Union County | New Jersey | 5,573 | 572,726 | 103 | county web map |
| 17 | City of Manassas Park | Virginia | 5,393 | 16,361 | 3.0 | VGIN Virginia Parcels map (Service View) |
| 18 | Cook County | Illinois | 5,384 | 5,087,072 | 945 | county web map |
| 19 | Nassau County | New York | 4,856 | 1,381,715 | 285 | county web map |
| 20 | Denver County | Colorado | 4,681 | 716,577 | 153 | county web map |
4 of the 20 are independent cities and 6 are New York City boroughs.
The 10 least densely populated
| # | County or equivalent | State | People per sq mi | 2023 pop. | Land (sq mi) | Parcel viewer |
|---|---|---|---|---|---|---|
| 1 | Yukon-Koyukuk Census Area | Alaska | 0.04 | 5,129 | 145,576 | no verified public viewer listed yet |
| 2 | Lake and Peninsula Borough | Alaska | 0.06 | 1,331 | 23,832 | ArcGIS Experience Builder |
| 3 | Loving County | Texas | 0.06 | 43 | 669 | appraisal district map |
| 4 | Yakutat City and Borough | Alaska | 0.09 | 687 | 7,623 | Alaska Statewide Parcels layer in ArcGIS Map Viewer |
| 5 | Copper River Census Area | Alaska | 0.1 | 2,674 | 24,692 | no verified public viewer listed yet |
| 6 | North Slope Borough | Alaska | 0.1 | 10,603 | 88,824 | Alaska Statewide Parcels layer in ArcGIS Map Viewer |
| 7 | Denali Borough | Alaska | 0.1 | 1,584 | 12,641 | Alaska Statewide Parcels layer in ArcGIS Map Viewer |
| 8 | Esmeralda County | Nevada | 0.2 | 736 | 3,582 | County Parcels in Nevada layer in ArcGIS Map Viewer |
| 9 | Northwest Arctic Borough | Alaska | 0.2 | 7,361 | 35,663 | no verified public viewer listed yet |
| 10 | Kenedy County | Texas | 0.2 | 343 | 1,459 | appraisal district map |
Alaska has no counties. Its entries are boroughs and census areas, the units the Census Bureau counts as county equivalents there.
What density tells you before you open a parcel map
- High density means small, crowded parcels. Expect condominium and co-op units, narrow city lots and parcel numbers tied to blocks and lots.
- Low density means big tracts and public land. Expect large ranch, forest or tribal and federal parcels, and long distances between addresses.
- Density is an average. A county can have a dense city and empty backcountry, so look at the parcel map itself for the spot you care about.
Connecticut is the one awkward fit. The 2020 Gazetteer still has its 8 historic counties, but since 2022 the Census Bureau has used Connecticut's 9 planning regions as its county equivalents, so the 2023 estimates are by planning region. Rankings that need both land area and a 2023 population leave Connecticut out.
Related guides
- Largest counties in the US by land area
- Most populous counties in the US
- Largest county in each state
- Smallest county in each state
- Smallest counties in the US
- Least populated counties in the US
- How many counties are in the US
Sources
- U.S. Census Bureau Gazetteer files, 2020 county land and water area (50 states and the District of Columbia; Puerto Rico's municipios are left out).
- U.S. Census Bureau, Population Estimates Program, county totals, Vintage 2023 (July 1, 2023 estimates)
- Platbookmapper county GIS directory (live data file behind our county pages, pulled October 22, 2026) for each official parcel viewer.