The eternal calendar complication is an advanced version of a perpetual calendar that accounts for the Gregorian calendar’s leap year exceptions over a 400-year cycle. This means it remains accurate for significantly longer periods without requiring manual adjustments.

IWC Schaffhausen, renowned for combining technical precision with innovative design, unveiled the Portugieser Eternal Calendar in 2024. Let’s take a closer look at what sets the eternal calendar apart and how IWC has contributed to the evolution of the perpetual calendar complication.

IWC Schaffhausen significantly impacted the watch industry in 1985 when Kurt Klaus developed a groundbreaking perpetual calendar module. Unlike earlier designs that required multiple pushers for adjustments, Klaus’s system allowed all calendar functions to be set through the crown, making it more user-friendly. This invention established IWC as a leader in perpetual calendar technology.

Building on this legacy, IWC has continuously improved its perpetual calendars which are programmed to remain accurate until the year 2100, when the next irregularity in the Gregorian calendar takes place.

Anticipating this exception, IWC introduced the Portugieser Eternal Calendar in 2024. The Eternal Calendar watch is programmed until the year 3999, accounting for two additional rules of the Gregorian calendar—the 100-year rule and the 400-year rule. To achieve this, IWC developed a highly precise 400-year wheel, a mechanism that completes a full rotation only once every four centuries.

This high complication timepiece features a reengineered moon phase display with exceptional accuracy, deviating by just one day every 45 million years. This extraordinary technical achievement underscores IWC's mastery of horological engineering and its unwavering commitment to pushing the boundaries of watchmaking excellence.

Price on Request

Case Material: Platinium

Bracelet: Leather Strap

Buckle: Folding buckle

Water resistance: 50 meters

Case Size: 44.40mm

Movement: Automatic

Power reserve: 168 hours

Complications: Date, Day of the Week, Month, Year, Moon Phases, Power Reserve Indicator, Eternal Calendar

Reference: IW505701

Manifest eternity on your wrist with the IWC Eternal Calendar watch. Experience the art of horology firsthand at King Jewelers' exclusive IWC Schaffhausen Boutique in the Mall at Green Hills, or visit our Nashville showroom for a personalized consultation. Discover the legacy of IWC timepieces and find the perfect masterpiece to elevate your collection today.