New Tecumseth is a town in south-central Ontario, in the County of Simcoe. While it is not officially a part of the Greater Toronto Area, it is counted, in terms of the Census, as being a part of the Toronto CMA and is, unofficially at least, considered to be a part of the GTA. The main centres in New Tecumseth are the towns of Alliston, Tottenham , and Beeton.

According to the 2001 Statistics Canada Census:

• Population: 26,141
• % Change (1996-2001): 14.1
• Dwellings: 9,588
• Area (sq. km.): 274.18
• Density (persons per sq. km.): 95.3