A series of experiments comparing rapeseed oil, soybean oil, and tallow as energy supplements in turkey finishing diets showed that rapeseed oil was as satisfactory an energy supplement as the other fat sources. There was no indication of a growth depressant effect from the rapeseed oil with birds of this age. Feed:gain ratio, carcass finish, and metabolizable energy values from the rapeseed-oil-supplemented diets were all significantly (P < 0.05) better than from the basal diets, but did not differ significantly from those supplemented with the other fat sources. There was, however, a trend towards a slightly higher metabolizable energy value for the rapeseed oil diets compared with the soybean-oil- and tallow-supplemented diets.