Little Elm is a city in Denton County, Texas, United States, and a part of the Dallas-Fort Worth Metroplex. It is an extended suburb of Dallas. The population was 3,646 at the 2000 census. By the 2010 census, the city total had jumped to 25,898, making Little Elm one of the fastest growing municipalities in Texas since 2000 in terms of percentage. At the entrance to the city limits, population signs reflect a size of more than 31,000 as of 2013.