A day-date calendar mechanism comprises a day-date drive wheel having a pair of tabs extending upwardly therefrom. The date wheel is coupled to an hour wheel and driven thereby so that the tabs engage, respectively, one of the 7 day dial teeth and one of the 31 date dial teeth to effect movement of said teeth during a 24 hour period. The mechanism is designed so that the date advances slowly prior to midnight and jumps approximately two-thirds pitch at midnight, while the day advances slowly past midnight and jumps approximately one-half pitch at about 12:40 a.m., thus minimizing the loading on the watch drive means. The day and date may be set in relation to each other since the date does not change when the hands are rotated counterclockwise past midnight while the day indication reverts by one day.
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