The Township of Woolwich is a rural township in Southwestern Ontario, Canada, considered as a municipality. The Township is located in the northeast part of Waterloo Region and is made up of 10 small communities, with Elmira, Ontario the largest and St. Jacobs, Ontario the second largest. The population at the time of the 2021 Census was 26,999, up from the 2016 population of 25,006. Waterloo Region is still home to the largest population of Old Order Mennonites in Canada, particularly in the areas around St Jacobs and Elmira. They are often seen on the local roads using their traditional horse and buggy transportation; many also use horses to pull the implements in their farm fields.

Elmira is the largest community in the township of Woolwich, Ontario, Canada. It is 15 kilometres (9 mi) north of the city of Waterloo near the Regional Municipality of Waterloo's northern border with Wellington County. The community was listed in the 2016 Canadian census as having a population of 10,161.