Merrill is a city in and the county seat of Lincoln County, Wisconsin, United States. It is located to the south of and adjacent to the Town of Merrill. The population was 9,661, according to the 2010 census. Merrill is part of the United States Census Bureau's Merrill MSA, which includes all of Lincoln County. Together with the Wausau MSA, which includes all of Marathon County, it forms the Wausau-Merrill CSA.
Merrill was first inhabited by the Chippewa Native Americans. The first European settlement there was a logging town named Jenny Bull Falls. By 1843, a trading post was constructed near the town; John Faely was the first settler. Within four years a dam, started by Andrew Warren, was constructed over the Wisconsin River. Warren then established the first mill powered by the dam, and other saw mills in the area. In 1870, T. B. Scott succeeded Warren, and the mill soon became increasingly successful.