Perth was a constituency of the House of Commons of the Parliament of the United Kingdom from 1832 to 1918, 1918 to 1950, and 1997 to 2005. From 1832 to 1918 it was a burgh constituency. From 1918 to 1950, and 1997 to 2005, it was a county constituency. During each of the three periods it elected one Member of Parliament (MP).