IWC Schaffhausen Portugieser Eternal Calendar

Technical specifications


  • Hours
  • Minutes
  • Seconds
  • Perpetual Calendar
  • Day
  • Date
  • Month
  • Years
  • Double Moon™
  • Power Reserve


  • Self Winding/Automatic
  • Manufactured
  • Swiss Made


  • Round
  • Platinum
  • Polished
  • 15.00mm
  • 44.40mm


  • Sapphire

Water resistance

  • 5.00atm / 50.00m / 165.00ft


  • Deployment Buckle
  • Platinum


  • Alligator
  • Black


  • 2024

Official description

IWC Schaffhausen introduces the Portugieser Eternal Calendar at Watches and Wonders Geneva. Drawing on the extensive calendar expertise it has acquired since introducing the perpetual calendar almost four decades ago, IWC now pushes the boundaries once again with its first secular perpetual calendar. In addition to recognising the different lengths of the months and adding a leap day every four years, the Portugieser Eternal Calendar also takes into account the Gregorian calendar’s complex leap-year exception rules. A newly engineered 400-years gear ensures that the calendar automatically skips three leap years over four centuries – an event which will occur for the first time in the year 2100. Another key feature of this watch is the extremely precise moon phase display. Thanks to a newly developed reduction gear, the Double Moon™ phase display will only deviate from the moon’s orbit by one day after 45 million years. The Portugieser Eternal Calendar features an intricately finished platinum case and a black alligator leather strap from Santoni. The extensive use of glass elements such as a glass dial and double box-glass sapphire crystals showcases the ingenious mechanism inside. The increased transparency also creates a unique sense of lightness, airiness and understated elegance.