Lesslie is a census-designated place located in York County, South Carolina, United States, southeast of the city of Rock Hill. In 2010, Lesslie had a total population of 2,882 people. While Lesslie is sometimes considered to be a town, it is not incorporated and does not have a town council or mayor. Lesslie is a fast-growing suburban area a part of th…Lesslie is a census-designated place located in York County, South Carolina, United States, southeast of the city of Rock Hill. In 2010, Lesslie had a total population of 2,882 people. While Lesslie is sometimes considered to be a town, it is not incorporated and does not have a town council or mayor. Lesslie is a fast-growing suburban area a part of the Charlotte Metro along Interstate 77, which can be accessed from exits 75 and 77.