Heidelberg Wellesley is an unincorporated community in Ontario, Canada, in the Township of Wellesley, Regional Municipality of Waterloo. It is recognized as a designated place by Statistics Canada.
In the 2021 Census of Population conducted by Statistics Canada, Heidelberg Wellesley had a population of 392 living in 149 of its 150 total private dwellings, a change of 1.3% from its 2016 population of 387. With a land area of 0.38 km2 (0.15 sq mi), it had a population density of 1,031.6/km2 (2,671.8/sq mi) in 2021. [1]