Day of the month display mechanism for watch movement, comprising two mobiles (1), each bearing a sequence of digits (10). The two mobiles are disposed in such a manner that, at least for certain dates, the day of the month (3) displayed to the user corresponds to the combination of indications borne by the first mobile (1) and of indications borne by the second mobile (2), whilst for other dates, the day of the month (3) corresponds to the combination of two digits borne by the same mobile (2). The second mobile (2) is driven by the first mobile (1) through a star wheel (50) held by a jumper (51) to prevent the undesired rotation of said star. A banking element (511) is arranged in a manner to prevent said jumper from passing directly from one tooth (501) of the star to a non-adjacent tooth when the date changes.