Bluffton is a town in Beaufort County, South Carolina, United States. The population is 37,000 and center of the Bluffton Urban Cluster with a total population of 5,848. However, this separated urban area currently defined as Bluffton is quickly becoming contiguous to that of the significantly larger Hilton Head Island adjacent to it. As designated by the U.S. Census Bureau, Bluffton is included within the Hilton Head Island–Beaufort Micropolitan Statistical Area. Bluffton is known for its rapid development, currently among the fastest in the state of South Carolina. A large amount of land has been annexed in the last few years leaving behind the old "One Square Mile" adage.