Haute Complication: Patek Philippe’s New Ref. 5236P-001 In-line Perpetual Calendar

Haute Complication: Patek Philippe’s New Ref. 5236P-001 In-line Perpetual Calendar

Adrienne Faurote
By Adrienne Faurote April 13, 2021

The perpetual calendar is a complication that has always held an important place in the history of Patek Philippe. In 1925 the brand already launched its very first perpetual calendar wristwatch, and in 1941 the brand introduced Ref.1518,  combining a perpetual calendar with a chronograph, something that has never been done before in a watch made in series. Patek Philippe always had a strong presence when it came to pocket watches as well, and in 1972 they introduced a novel perpetual calendar with in-line display. Now, part of its rich legacy in this field merges with the introduction of the new Ref. 5236P-001 In-line Perpetual Calendar.

Fitted in a 41.3mm large Calatrava-case, made from platinum, and combined with a blue lacquered dial with black gradation is the Ref. 5236P-001 quite subtle in its appearance. This is for good reason as it sets perfectly the stage to let the unique in-line perpetual calendar function shine. Day, date, and month are positioned in a single window next to each other under the Patek Philippe brand name. This symmetry is continued at the lower part of the dial, where the subdial for the seconds also houses the moon phase indicator. It is flanked on the right with the leap-year indicator, while whether it is day or night is shown through the window on the left. With this balanced look, Patek Philippe makes the Ref. 5236P-001 look simple, while it is, in fact, a very complex watch.


No less than three new patents are incorporated in the movement. To make this unique display of the perpetual calendar possible, Patek Philippe used caliber 31-260 as a base movement. This is good news, as this movement is a reliable performer and looks especially well. Patek Philippe tuned to movement to make it perfect for the Ref. 5236P-001, by replacing the micro-rotor from gold to platinum for more mass and increase the rate to 4 Hz/28,800 vph. This results in better rate stability and hence increased precision. The movement now also uncouples the automatic winding system as soon as the watch is wound manually to reduce wear. With the Ref. 5236P-001, Patek Philippe is continuing its legacy as a pioneer in perpetual calendars and confirming the important place that this complication holds within its collection.