Abstract: Method and apparatus for liquefying a hydrocarbon stream such as natural gas from a feed stream. The method comprises at least the steps of: first cooling the feed stream (10) against a first cooling refrigerant being cycled in a first cooling refrigerant circuit (100), wherein the first cooling refrigerant comprises >90 mol % propane, second cooling the cooled gas stream (20) to obtain a liquefied stream (60) against a first mixed refrigerant being cycled in a first mixed refrigerant circuit (200), wherein said second cooling is in two or more heat exchangers (42, 44), at least two of which are operating at different pressures and sub-cooling the liquefied stream (60) against a second mixed refrigerant or against a nitrogen refrigerant being cycled in a sub-cooling refrigerant circuit (300), thereby obtaining a sub-cooled hydrocarbon stream (70).