Refrigerant compositions are disclosed which comprise: (a) pentafluoroethane, octafluoropropane, trifluoromethoxydifluoromethane or hexafluoro-cyclopropane, or a mixture of two or more thereof, in an amount of at least 35 % based on the weight of the composition, (b) 1,1,1,2- or 1,1,2,2-tetrafluoroethane, trifluoromethoxypentafluoroethane, 1,1,1,2,3,3-heptafluoropropane or a mixture of two or more thereof, in an amount of at least 30 % by weight based on the weight of the composition and (c) n-butane or isobutane, in an amount from 1 % to less than 2.3 % by weight based on the weight of the composition.