Pre-SIHH 2015: IWC Portugieser Annual Calendar ref. 5035 Watch

By Osheen Arakelian

The new Portugieser Annual Calendar brings together two firsts for IWC and three masterstrokes of haute horlogerie in a single case: the newly developed annual calendar closes the gap between the perpetual calendar and the simple date display. The new IWC-manufactured 52850 calibre has two barrels that keep the new function supplied with ample energy and still has enough left for a 7-day power reserve.

IWC is no stranger to producing quality and eye-catching complications as part of their Portugieser collection of timepieces. From the minute repeater introduced in 1995 to the 7-day power reserve in 2000 and the constant force tourbillon more recently in 2011 – the Portugieser collection is one of the most loved in the world of horology. In 2015, IWC has stepped it up another notch with the introduction of yet another complication, the Annual Calender. The annual calendar has taken the white coats at IWC 5 years to develop and design, but with so much experience producing in-house complications, it was a challenge they were willing to tackle and with great success. The success is down to the right choice of movement as a base to work from and that is the reason for choosing this robust movement. The 52850 calibre movement with its high torque is better able to supply enough energy to the movement’s three display discs to power the annual calendar accurately.


How the annual calendar functions is through a series of mechanisms and is explained best by IWC themselves: the hour wheel sets in motion the date advance wheel, which is equipped with two different advance fingers. One of the fingers is responsible for the date and month displays, the other for the weekday display. Every day, towards midnight, the date is moved forward with the hep of the upper advance finger. The month display and the programme wheel, which defines the lengths of the various months, are controlled by 2 pins on the date disc. The first of these pins advances the programme wheel by one division. A feeler on the advance lever recognises months with 30 days by a deeper notch on the program wheel and provides more space for it to switch. The following day, the advance lever ensures that the date moves forward by 2 days. The second pin in the date disc sets the new month.


It truly is a wonderful complication and so intricate in its design that you just have to marvel at its workings. However, for me personally, the most important aspect of the timepiece is the dial. To free up as much space as possible on the dial, IWC designers replaced the indices from 11 o’clock to 1 o’clock with the three display discs. The American order of the date shown is not because they like Americans more than the rest of the world, but because it pays homage to F.A. Jones, IWC’s American founder. The rest of the design including the slim feuille hands, railway-track-style chapter ring and almost unchanged Arabic numbers give the Portugieser Annual Calender a familiar feeling and keep it well grounded to the IWC Portugieser family. Lastly, the final albeit subtle change we see is the small seconds subdial, that has been repositioned from 6 o’clock to the 9 o’clock position, providing a better aesthetic appeal and giving the watch greater overall balance on the dial. The power-reserve indicator is also located at 6 o’clock.


The IWC Portugieser Annaul Calender is available in a number of references including Ref. IW503501: case in stainless steel, silver-plated dial, black alligator strack, folding clasp in stainless steel; Ref. IW 503502: case in stainless steel, midnight blue dial, black alligator strap, folding clasp in stainless steel and Ref. IW503504: case in 18-carat red gold, silver-plated dial, black alligator strap, folding clasp in 18-carat red gold.


A stunning new addition to the Portugieser range from IWC and definitely a winner in my books. For more info, please visit

Osheen Arakelian – Contributing Editor

Drawing on a lifelong love of horology and a more recent introduction to appreciation of fine whisky, Osheen brought the two together with watch & whisky. He is proprietor of the site, which covers everything related to watches and whisky. In between completing a degree in commercial law and supporting a rich social life, he is out and about attending all the latest watch and whisky events Sydney has to offer. His passion has also taken him around Australia attending a number of events and he hopes to continue his career in the watch industry on a more serious level after he graduates. Read his articles here.