A retractable step assembly (400) for a cab (C) for a mobile machine includes a leg (450) slideably received in a through-hole (408) in a platform (58) of a cab (C). An upper end (452) of the leg (450) is fixed to a lower end (434) of a stretchable spring (430) whose upper end (432) is fixed. A step (470) is mounted to the lower end (454) of the leg (450). The leg (450) is movable between a retracted position and an extended position in which the step (470) is nearer to the ground than in the retracted position. The step (470) can be stepped on by an operator to move the leg (450) to the extended position to thereby allow the operator to exit the cab (C) by stepping on the step (470). The leg (450) can be unlatched by the operator in the cab (C) to return to the retracted position under action of the spring (430).