The fastest-growing counties in Utah, ranked.

Tooele County spreads across a wide valley floor west of the Oquirrh Mountains, with the county seat and largest town, Tooele, near its center. It grew faster than any other county on this list since the 2020 count as people looked west of the metro for ground that still had room. That pace shows up in a steady stream of newer homes and a market that moves quickly.

Washington County fills Utah's southwest corner with low desert and red rock, centered on St. George, which is both its seat and its largest town. Hot summers and mild winters keep it a year-round destination, and Zion National Park lies close at its edge. Growth here has run strong for decades and stayed near the top of the state after 2020, which keeps new construction moving and the market competitive.

Iron County sits on a high mountain-valley floor around Cedar City, its largest town, with the county seat in Parowan to the north. Winters here run cold and snowy, Cedar Breaks National Monument lies in the high country above, and Brian Head ski area is up the mountain. Southern Utah University anchors Cedar City, and growth has pushed a steady run of newer neighborhoods through the valley.

Utah County runs down the west side of the Wasatch into Utah Valley, with Provo as its seat and largest city. Brigham Young University and Utah Valley University anchor its two biggest towns, and summer days run hot and dry. Growth of this size keeps the valley in constant building, with new subdivisions pressing out from Provo toward the county's north and south ends.

Juab County is a ranching and farming valley in central Utah along Interstate 15, with Nephi as its seat and largest town. The Little Sahara dunes east of the highway draw recreationists, and the county sits where the southern push out of Utah Valley meets open country. Its growth since 2020 puts it in the fast group, though the base it grows from is still a small one.

Box Elder County sits below the Wellsville Mountains at the north end of the Wasatch, with Brigham City as its seat and largest town. Golden Spike National Historical Park and Willard Bay State Park are both in the county, and the economy mixes agriculture with the corridor that runs toward Idaho. Growth has climbed steadily since 2020 as buyers look further north of the main metro.

Wasatch County anchors the valley around Heber City, its seat and largest town, on the east side of the Wasatch crest. Winters run long and cold, and the big Park City ski areas sit just across the county line in Summit County. Growth here has been strong as the Wasatch Back fills in, and the county's own home values have climbed with that demand.

Sanpete County is a broad farming valley in central Utah, with Manti as its seat and Ephraim as its largest town. Snow College sits in Ephraim, and Palisade and Yuba state parks lie at the valley's edges. The county has grown at a solid clip since 2020, pulling buyers who want lower home values than the Wasatch Front and the Wasatch Back carry.

Cache County fills the northern Utah valley around Logan, its seat and largest city, with Utah State University near the center of town. Winters are cold and inversions settle into the bowl, while the surrounding peaks hold the Beaver Mountain and Cherry Peak ski areas. Growth has been steady as more of the Wasatch Front looks north for room, and the county's home values sit below Salt Lake County's.

Morgan County is a narrow valley along the Weber River between the Wasatch Front and the mountains to the east, with the town of Morgan as both seat and largest community. Winters bring heavy snow, and East Canyon and Lost Creek state parks sit in its high country. It is the smallest county on this list, so a modest gain in people reads as a large percentage.

Millard County spreads across the broad Pahvant Valley in central Utah, with Fillmore as its seat and Delta as its largest town. The Territorial Statehouse in Fillmore preserves the county's early history, and Interstate 15 crosses its west side. Growth since 2020 sits near the middle of this ranking, steady rather than dramatic.

Uintah County sits in the high-desert Uinta Basin of eastern Utah, with Vernal as its seat and largest town. Dinosaur National Monument lies just outside town, and Steinaker and Red Fleet reservoirs carry the local water recreation. Energy work has long driven the economy, and growth has held a steady pace since 2020 with home values staying lower than most of the state.

Duchesne County covers the western Uinta Basin, with Roosevelt as its largest town and Duchesne as the seat. Starvation Reservoir draws anglers and boaters, and ranch land spreads across the valley floor. Growth here has been modest and steady, in line with a county where energy and agriculture set the pace and home values run low.

Sevier County runs down the Sevier Valley in central Utah, with Richfield as both its seat and largest town. Interstate 70 and Interstate 15 meet at the county's west end near Cove Fort, which makes it a true crossroads. Growth has been mild since 2020, and the housing market here runs calmer than it does in the fast movers.

Weber County centers on Ogden, its seat and largest city, on the valley floor where the big Wasatch canyons open to the east. Snowbasin, Powder Mountain, and Nordic Valley ski areas sit up those canyons, and Weber State University anchors the city. Growth has run at a moderate pace, with Ogden's older neighborhoods seeing steady turnover rather than new sprawl.

Davis County hugs the bench between the Wasatch and the Great Salt Lake, with Layton as its largest city and Farmington as the seat. Antelope Island State Park sits just offshore, and Hill Air Force Base and Lagoon anchor the county's economy on either end. It is one of the older suburban counties on the Wasatch Front, which keeps its growth moderate and its market steady.

Salt Lake County is the state's population center, with Salt Lake City as its seat and largest city and the Cottonwood ski areas up its east-side canyons. Intermountain Health, the University of Utah, state government, and Delta Air Lines anchor a deep job market. The county's growth percentage looks small only because it started this period as the largest county in Utah by a wide margin.

Summit County is the Wasatch Back's resort county, with Park City as its largest town and Coalville, the seat, up the valley to the north. Park City Mountain and Deer Valley sit in the county, and Rockport and Echo state parks hold its reservoirs. Growth has been light since 2020, in line with a county where resort land and conservation ground already cover much of the map.

Carbon County sits in the high-desert Castle Valley corridor of eastern Utah, with Price as its seat and largest town. Coal mining built the county, and Utah State University Eastern now anchors the town alongside that energy history. Growth since 2020 has been nearly flat, which keeps the housing market calm and home values near the bottom of this list.

San Juan County is Utah's southeastern corner, a high, wide country of red rock at the base of the Abajo Mountains, with Blanding as its largest town and Monticello as the seat. Canyonlands' Needles district, Natural Bridges, Hovenweep, and Bears Ears all fall inside its borders. It has grown the least of any county here since 2020, and its home values sit among the most affordable in the state.