The annual calendar, I would argue, is watchmaking’s most useful feature, next to the power reserve indicator, yet it is not all that common. The Annual Calendar, which displays day, date and month, automatically accounts for the variation in the number of days in each month. Only one manual correction needs be made each year, (for the month of February in non-leap years). Legibility is key with an annual calendar, since there is a lot of information to convey on a small canvas. Zenith, for example, adds a small seconds and chronograph function and still manages to look sleek and classic. Technically, the Cartier Rotonde Annual Calendar featured here was introduced in 2012, not 2013, but we like its unique arrangement of information so much we’re including it in this year’s list anyway.
Patek Philippe has added a moonphase indicator to the Nautilus 5726A, with a 24-hour index circling it. It contains mechanical self-winding caliber 324 S QA, with day, date and month in apertures. In steel, it is water resistant to 120 meters.
Rotonde de Cartier Annual Calendar, with caliber 9908 MC, with a multi-layered dial indicating months above the Roman numerals on the main dial and days of the week on the inner main dial. A red line (the tips of hammer-shaped hands) indicate the current day and month.
A. Lange & Söhne Saxonia Annual Calendar in platinum, with day, date, month and moonphase indicators. With a patented zero-reset function that stops the seconds hand when resetting. With automatic caliber L085.1.
Zenith Captain Winsor with gold Arabic numerals on a white dial. With El Primero automatic caliber 4054, with small seconds at 9 o’clock and a chronograph function with minute totalizer, in addition to day, date and month.
Girard-Perregaux Annual Calendar and Equation of Time, with date and month, equation of time index and small seconds hand, in 18k gold, with automatic caliber GP03300-0010.