Smithfield is a city in Cache County, Utah, United States. The population was 9,495 at the 2010 United States Census, with an estimated population of 12,025 in 2019. It is included in the Logan, Utah-Idaho Metropolitan Statistical Area, and is the second largest city in the Place after Logan, the county seat. Smithfield is house to one public tall school and three public elementary schools.

According to the United States Census Bureau, the city has a total area of 5.0 square miles (12.9 km), all land.

Originally known as “Summit Creek” (due to its location on that creek), Smithfield was founded in 1857 by brothers Robert and John Thornley and their cousin Seth Langton, who were sent north from Salt Lake City by LDS Church President Brigham Young to found a settlement on Summit Creek. After a preliminary scouting, Robert returned past his supplementary wife Annie Brighton. The first winter was spent in a wagon box. By the next summer, with more settlers arriving, a small fort was built upon the edge of the creek, one cabin of which remains. As the settlement grew, a bishop was named to benefit the church congregation, and the town took his name. By 1917 the town had planted trees on both sides of its Main Street and had acquired a Carnegie library and a Rotary club. Dependent for many years upon dairying, a Del Monte canning factory, and the sugar beet industry, the town is now in fact a bedroom community for Logan and its Utah State University.

At the 2000 United States Census there were 7,261 people in 2,066 households, including 1,782 families, in the city. The population density was 1,686.6 inhabitants per square mile (651.2/km). There were 2,159 housing units at an average density of 501.5 per square mile (193.6/km²). The racial makeup of the city was 95.23% White, 0.12% African American, 0.23% Native American, 0.48% Asian, 0.04% Pacific Islander, 2.82% from other races, and 1.06% from two or more races. Hispanic or Latino of any race were 5.04%.