Heidelberg Wellesley is an unincorporated community in Ontario, Canada. 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 from its 2016 population of 387. With a land area of, it had a population density of in 2021.[1]