Utah ( YOO-tah, YOO-taw) is a landlocked state in the Mountain West subregion of the Western United States. It is one of the Four Corners states, sharing a border with Arizona, Colorado, and New Mexico. It also borders Wyoming to its northeast, Idaho to its north, and Nevada to its west. In comparison to all the U.S. states and territories, Utah, with a population of just over three million, is the 13th largest by area, the 30th most populous, and the 11th least densely populated. Urban development is mostly concentrated in two regions: the Wasatch Front in the north-central part of the state, which includes the state capital, Salt Lake City, and is home to roughly two-thirds of the population; and Washington County in the southwest, which has somewhat more than 180,000 residents. Most of the western half of Utah lies in the Great Basin.

Utah has been inhabited for thousands of years by various indigenous groups, such as the ancient Puebloans, the Navajo, and the Ute. The first Europeans to arrive - in the mid-16th century - were the Spanish. Because of the region's challenging geography and harsh climate, it only became a peripheral part of New Spain (and later of Mexico). Even while it was Mexican territory, many of the Utah region’s earliest European settlers were from the United States; notable among these were Mormons who were fleeing marginalization and persecution in the United States and arrived via the so-called Mormon Trail. In 1848, after the Mexican–American War, the region was annexed by the U.S., becoming part of the Utah Territory, which included what later became Colorado and Nevada. Disputes between the dominant Mormon community and the federal government delayed Utah's admission as a state: in 1896, after it agreed to outlaw polygamy, it was admitted as the 45th state.

People from Utah are known as Utahns. Slightly over half of all Utahns are Mormons, the vast majority of whom are members of the Church of Jesus Christ of Latter-day Saints (LDS Church), which has its world headquarters in Salt Lake City; Utah is the only state where a majority of the population belongs to a single church. The LDS Church greatly influences Utahn culture, politics, and daily life, though since the 1990s the state has become more religiously diverse as well as secular.

Utah has a highly diversified economy, with major sectors including transportation, education, information technology and research, government services, mining, multi-level marketing, and tourism. Utah has been one of the fastest growing states since 2000, with the 2020 U.S. census confirming the fastest population growth in the nation since 2010. St. George was the fastest-growing metropolitan area in the United States from 2000 to 2005. Utah ranks among the overall best states in metrics such as healthcare, governance, education, and infrastructure. It has the 12th-highest median average income and the least income inequality of any U.S. state. Over time and influenced by climate change, droughts in Utah have been increasing in frequency and severity, putting a further strain on Utah's water security and impacting the state's economy.