Summit County area

Population and density of Summit County

The Census Bureau estimates that 43,141 people lived in Summit County on July 1, 2025. That ranks #1,150 of 3,222 county equivalents nationally and #10 of 29 in Utah. Since the April 1, 2020 estimates base of 42,356, the population has grown by 785 (+1.9%), compared with +8.2% for Utah as a whole.

With 1,870.7 square miles of land, that is 23 people per square mile (8.9 per km²), placing Summit County #2,205 nationally for density and #8 in Utah. The median county equivalent has 47 people per square mile; the Utah median is 11. Put another way, there are about 28 acres of land per resident.

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 Summit County

7 incorporated places lie at least partly in Summit County. Together they are home to 16,582 people (38.4%); the other 26,559 (61.6%) live outside any incorporated place, in unincorporated communities and rural areas.

The largest is Park City city, with 8,573 residents in the county (the city extends into 1 other county). The county seat, Coalville city, has 1,529 residents. Among places with at least 1,000 residents in 2020, Francis town grew fastest since then (+28.6%).

Population: U.S. Census Bureau Vintage 2025 subcounty estimates, counting only the part of each place inside Summit County. Land: 2026 Census Gazetteer, for the whole place even where it extends into other counties. How communities are listed.

Metropolitan area

Summit County is a central county of the Heber, UT Micropolitan Statistical Area. Its 2 county equivalents have 81,655 residents on 3,047.6 square miles of land; Summit County accounts for 61.4% of the land and 52.8% of the residents. By combined land it ranks #50 of 542 micropolitan areas, and #69 by population. It belongs to the Salt Lake City-Provo-Orem, UT-ID Combined Statistical Area.

ZIP codes

9 ZIP Code Tabulation Areas have land in Summit County, and each lies mostly inside the county.

829308401784024840338403684055840608406184098

ZIP Code Tabulation Areas are the Census Bureau’s approximations of USPS ZIP Code service areas, from the 2020 Census relationship files. Post-office-box and single-address ZIP Codes have no tabulation area.

Counties bordering Summit County

Summit County shares a land border with 8 county equivalents, including 2 in Wyoming. It has more land than 5 of them. The largest neighbor is Sweetwater County (10,427 mi²) and the smallest is Morgan County (609.2 mi²). Together with its neighbors, Summit County forms a block of 21,879 mi² of land, of which it holds 8.6%.

How big is Summit County compared with U.S. states?

Summit County has more land than 1 of the 50 states. It is about 1.8 times the land area of Rhode Island (1,033.9 mi²), while Delaware, the next larger state, has 1 times as much land (1,948.6 mi²). Utah’s county land could hold about 44 areas the size of Summit County.

Another way to picture it: the same land area would fill a square about 43.3 miles (69.6 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 Summit County?

Summit County has more land than 2,915 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 Summit County at #349 nationally by total area, 42 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 0.5%, compared with a national county-equivalent median of 1.2% — 0.6 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 Summit County in the national ranking. They can be in different states and are not necessarily geographic neighbors.

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.