Lewisville is a city in Denton County, Texas, United States. The 2000 United States Census placed the city's population at 77,737 and the 2010 Census placed it at 95,290, making it one of the fastest-growing city populations in the United States. It occupies 36.4 square miles (94 km²) of land and includes 6.07 square miles (15.7 km²) of Lewisville Lake.

Originally called Holford's Prairie, the origins of Lewisville date back to the early 1840s. The arrival of the town's first railroad in 1881 engendered its initial growth, and the expansion of the area's transportation infrastructure spurred further development in the early part of the 20th century. Lewisville incorporated in 1925, and when construction of Lewisville Lake was completed in the 1950s, the city began to expand rapidly.