Summit County is a county in Utah, United States, straddling the Uinta and Wasatch mountain ranges east of Salt Lake City. It had a population of 42,357 at the 2020 census and covers 1,882 square miles (4,870 km2), of which 1,872 square miles are land, centred near 40°53′N 110°58′W.
Coalville is the county seat, and its postal code is 84017. Park City, a former silver-mining town turned ski resort, is the county’s largest city. Summit County has five incorporated cities, one town, and eleven census-designated places. It observes Mountain Time and carries FIPS code 49043.
Towns & Villages in Summit County
Summit County’s population centers split between the mountain-resort corridor around Park City and the older ranching and railroad towns of the Coalville and Kamas valleys. The table below lists incorporated cities and towns, the county’s eleven CDPs (unincorporated but census-recognized), and smaller unincorporated places carried from the county’s historical settlement record. — marks a figure not independently verified.
| Place | Type | Pop. | ZIP |
|---|---|---|---|
| Coalville | City · seat | — | 84017 |
| Park City | City | — | 84060 / 84098 / 84068 |
| Kamas | City | — | 84036 |
| Oakley | City | — | 84055 |
| Francis | City | — | 84036 |
| Henefer | Town | — | 84033 |
| Snyderville | CDP | — | 84098 |
| Kimball Junction | CDP | — | 84098 |
| Jeremy Ranch | CDP | — | 84098 |
| Silver Summit | CDP | — | 84060 |
| Summit Park | CDP | — | 84098 |
| Peoa | CDP | — | 84061 |
| Marion | CDP | — | 84036 |
| Woodland | CDP | — | 84036 |
| Wanship | CDP | — | 84017 |
| Hoytsville | CDP | — | 84017 |
| Echo | CDP | — | 84024 |
| Silver Creek Junction | Unincorp. | — | 84098 |
| Keetley Junction | Unincorp. | — | 84060 |
| Samak | Unincorp. | — | 84036 |
| Upton | Unincorp. | — | 84017 |
| Wahsatch | Unincorp. | — | 84024 |
| Echo Resort | Unincorp. | — | 84024 |
| Castle Rock | Unincorp. | — | 84017 |
| Emory | Unincorp. | — | 84017 |
| Atkinson | Unincorp. | — | 84017 |
| Altus | Unincorp. | — | 84017 |
| Gogorza | Unincorp. | — | 84024 |
Silver Summit, Silver Creek Junction, and Keetley Junction all sit within a few miles of one another along the I-80/US-40 interchange south of Park City and are easy to confuse; Silver Summit and Kimball Junction are the census-recognized CDPs, while Silver Creek Junction and Keetley Junction are highway-crossroads names rather than platted communities.
ZIP Codes
- 84017 — Coalville (also serves Wanship, Hoytsville, Upton, Atkinson, Altus, Castle Rock, Emory)
- 84098 — Park City / Snyderville area (also serves Kimball Junction, Jeremy Ranch, Summit Park, Silver Creek Junction)
- 84060 — Park City (also serves Silver Summit, Keetley Junction)
- 84068 — Park City (PO box only)
- 84036 — Kamas (also serves Francis, Marion, Woodland, Samak)
- 84055 — Oakley
- 84061 — Peoa
- 84033 — Henefer (PO box only)
- 84024 — Echo (PO box only; also serves Wahsatch, Echo Resort, Gogorza)
Several smaller crossroads and summer-home settlements have no dedicated ZIP and use the nearest post office town’s code.
Geography
Summit County spans two mountain systems: the east-west Uinta Mountains along its eastern edge and the north-south Wasatch Range in the west. Gilbert Peak, at 13,448 feet, is the county’s and one of Utah’s highest points. The county contains portions of the Ashley and Wasatch-Cache National Forests and Rockport State Park on the Weber River, which drains the northern part of the county.
Summit County borders Rich County to the north, Wyoming to the northeast, Duchesne County to the east, Wasatch County to the south, Salt Lake County to the southwest, Morgan County to the west, and Weber County to the northwest.
Demographics
Summit County had 42,357 residents at the 2020 census. Park City and the unincorporated Snyderville Basin communities around it (Snyderville, Kimball Junction, Jeremy Ranch, Summit Park, Silver Summit) hold most of the county’s population; Coalville and the older ranching towns of the Kamas and Chalk Creek valleys are considerably smaller. Summit County’s median household income runs well above the Utah median of $93,421, driven by Park City’s resort economy and second-home market. Density works out to roughly 23 people per square mile of land, concentrated overwhelmingly around Park City.
Economy & Local Life
Tourism and real estate dominate the county’s economy, anchored by Park City Mountain Resort and Deer Valley Resort, two of the largest ski areas in North America, plus the annual Sundance Film Festival, which is based in Park City each January. Away from the resort corridor, ranching and hay farming continue in the Kamas Valley and along the Weber River near Coalville, and Rockport and Echo reservoirs support recreational fishing and boating.
History
Summit County was created by the Utah territorial legislature in 1854 and organized in 1861, one of Utah’s original counties. Its name refers to the mountain summits that dominate its terrain. Coalville grew around 19th-century coal mining along the Weber River, while Park City boomed as a silver-mining camp beginning in the 1870s before its 20th-century transition to skiing, culminating in hosting Olympic snowboarding and other events during the 2002 Winter Olympics.
Getting There
Interstate 80 crosses the county east-west through Coalville, Wanship, and Park City’s Kimball Junction; US-40 runs southeast toward Heber City and the Uinta Basin; US-189 connects Kamas to Provo Canyon.
- Salt Lake City — 32 miles west of Park City
- Heber City — 17 miles south of Park City
- Evanston, Wyoming — 22 miles north of Coalville
- Ogden — 35 miles northwest of Coalville
Salt Lake City International Airport, about 35 miles from Park City via I-80, is the nearest commercial airport.
Frequently Asked Questions
Where is Summit County, Utah?
It lies in northeastern Utah, east of Salt Lake City, spanning the Uinta and Wasatch mountain ranges.
What is the population of Summit County?
42,357 people at the 2020 census.
How big is Summit County?
1,882 square miles (4,870 km2), of which 1,872 square miles are land.
What is the county seat of Summit County?
Coalville is the county seat.
How many towns are in Summit County?
Five incorporated cities, one town, and eleven census-designated places.
What ZIP codes are in Summit County?
Nine ZIP codes, including 84017 (Coalville), 84098 and 84060 (Park City area), 84036 (Kamas), and 84055 (Oakley).
What is Summit County known for?
Park City’s ski resorts and the Sundance Film Festival, held there each January.
More counties in this state: Towns and villages in Utah.