Mean monthly and annual maps of evaporation over Canada have been prepared, and examples are presented. The maps represent time and space averages of evaporation from natural open water bodies having negligible heat storage. The analysis is based on 5‐year class A evaporation pan data supplemented by 10‐year climatologic data from 100 stations across Canada. The Christiansen formula is shown to be superior to other formulas tested for approximating pan data from other standard climatologic observations. The analysis takes account of the seasonal effects of freeze‐up and breakup on the availability of open water. A zonal classification of lake evaporation that emphasizes the large‐scale climatic variations in this parameter across Canada is proposed.