Westbury was a parliamentary constituency in Wiltshire from 1449 to 2010. It was represented in the House of Commons of England until 1707, and then in the House of Commons of Great Britain from 1707 to 1800, and finally in the House of Commons of the Parliament of the United Kingdom from 1801 until 2010.

Westbury is a market town and civil parish in west Wiltshire, England. The town lies below the northwestern edge of Salisbury Plain, about 4 miles (6 km) south of Trowbridge and a similar distance north of Warminster.