The Portuguese Perpetual Calendar brings together two signature traits from IWC – the classic Portuguese watch design and the brand’s innovative user-friendly perpetual calendar complication. Along with the appealing aesthetic and functionality combination, this particular luxury watch is fashioned from stainless steel and was produced in a limited run. Keep reading as we spotlight the striking IWC Portuguese Perpetual Calendar IW502308.

IWC Portuguese Perpetual Calendar IW502308
IWC Portuguese Perpetual Calendar IW502308

The Origins of the IWC Portuguese Perpetual Calendar Watch

In the 1930s, two businessmen from Lisbon, Portugal asked International Watch Company, better known as IWC, to create a timepiece as accurate as a marine chronometer but that could be worn on the wrist. To achieve this, the watchmakers at IWC had to encase the company’s most precise pocket watch movement, the Caliber 74, in a very large case. The result was an oversized (for the era) 41.5mm case, which housed a minimally styled dial. IWC called the watch the Ref. 325 and less than 700 pieces were made throughout its history, which ended in the early 1980s. 

In 1993, IWC revived the watch model to celebrate the brand’s 125th anniversary, aptly called the Portuguese Limited Edition Jubilee. This set the stage for the Portuguese (or Portugieser in German) model to become a mainstay in IWC’s catalog—where it remains today.

The groundbreaking Da Vinci Perpetual Calendar Chronograph

Turning back the clock a little to the eighties, it was in 1985 that IWC’s watchmaker Kurt Klaus debuted his groundbreaking perpetual calendar complication in the Da Vinci Perpetual Calendar Chronograph. Unlike other perpetual calendar movements that require an assortment of pushers and correctors, Kurt Klaus developed his mechanism so that all adjustments could be done via the winding crown. This is even more impressive when you consider that IWC’s perpetual calendar displays the date, day of the week, month, moon phase, and year in four digits. With continuous power, the perpetual calendar will indicate everything correctly until 2499 but if the watch stops running, adjusting the display is simple since the crown controls it all. 

Kurt Klaus’ invention firmly established IWC as a high horology brand, capable of producing some of the most intriguing mechanically complex watches in our modern era.

Somewhat surprisingly, it wasn’t until 2003 that IWC combined the Portuguese watch design with the perpetual calendar complication. For the first decade or so, IWC only offered precious metal versions of the Portuguese Perpetual Calendar. However, the introduction of the ref. IW502308 changed that.

Portuguese Perpetual Calendar IW502308

Introduced in 2014, the reference IW502308 was the first Portuguese Perpetual Calendar offered in stainless steel. Like its gold and platinum counterparts, the steel Portuguese Perpetual Calendar 5023-08 sports a generously sized 44.2mm case. However, stainless steel is noticeably lighter than precious metals for added comfort on the wrist.   

IWC Portuguese Perpetual Calendar IW502308
The ref. 5023-08 was the first stainless steel Portuguese Perpetual Calendar

The dial layout remains the same with three subsidiary dials at 3, 6, and 9 to indicate the date, month, and day. Furthermore, there’s also the power reserve indicator placed into the date subdial and the running seconds hand tucked into the day subdial—both furnished with red hands for pops of color. At 7:30 sits the four-digit year indicator. The reference 5023 is the single moon display variant (compared to the 5032, which is the double moon edition) with the moon phase placed at 12 o’clock. 

Protecting the silver-plated dial is a convex scratch-resistant sapphire crystal, which has been treated with anti-reflective coating on both sides. Likewise, the caseback is also furnished with a sapphire crystal for a view of the movement inside the watch. Powering the Portuguese Perpetual Calendar 5023-08 is the Caliber 51613 automatic movement with a seven-day power reserve. As expected, the in-house movement is intricately finished, decorated with the Côtes de Genève motif.

IWC Portuguese Perpetual Calendar IW502308
IWC Caliber 51613 has a seven-day power reserve

The Portuguese Perpetual Calendar reference 5023-08 is fitted with a dark brown alligator strap, equipped with a stainless steel deployant clasp.

Only 500 Portuguese Perpetual Calendar IW502308 examples were produced, exclusively sold at IWC boutiques. And now is your chance to own one as Gray & Sons is offering a rare pre-owned IWC Portuguese Perpetual Calendar IW502308 in our current catalog, complete with box and papers.