30 Years Patek Philippe Annual Calendar: The Ultimate Collector’s Guide

Serving progress, year after year

“For 30 years, the Patek Philippe annual calendar mechanism has been the most elegant solution to a problem that has preoccupied humanity since the dawn of timekeeping. If you are a serious watch collector, you will certainly be familiar with this question from the uninitiated: if you were only allowed to keep one watch for the rest of your life, which would it be? Of course, the question is theoretical, even if history has repeatedly shown instances where people were grateful to make it through with nothing but a watch on their wrist. Yet, Patek’s Annual Calendar would be a prime candidate for the answer: ironically, at the very dawn of the digital age, perhaps one of the most practical complications for mechanical wristwatches was developed.”

Let’s take a step back in time

Fun fact: Patek Philippe never claimed to have ‘invented’ the annual calendar. However, nothing quite like it existed when the Geneva-based development department set to work in the early 1990s. The context: the legendary Calibre 89 pocket watch had recently been created for the brand’s 150th anniversary. This timepiece sparked a resurgence of interest in complications across the entire industry and subsequently encouraged many manufacturers to try their hand at this segment once again.

In the preceding decades, triggered by the Swiss watch crisis and the boom in quartz watches, complicated mechanical wristwatches had all but vanished, and only a few customers remained interested in such models.

As one of very few companies, the Stern family held fast to complex mechanics: Patek Philippe had never stopped manufacturing complications. It was the decisive step that solidified the manufacture’s leading position in this field to this day and, thirty years on, provides it with a formidable technical edge.

The direct consequence of this approach was the production of complex mechanical watches in the decade following the anniversary, while many Swiss competitors were still resting on mass-produced movements. With the comeback of mechanical watchmaking, questions quickly arose regarding an increasing market saturation in the top-tier segment. No one at the time foresaw its meteoric rise, and it seemed sensible to broaden the pool of potential customers by offering complications that were not only more affordable but also easier to operate.

The first annual calendar was introduced in Basel in 1996

The launch of an Annual Calendar caused an immediate sensation among collectors: first presented in Basel in the spring of 1996, the newcomer was crowned ‘Watch of the Year’ by the Swiss magazine Montres Passion the following autumn. In a world transitioning into the digital age, awards of this nature were still a significant event. As a long-standing member of the jury, the British watch expert Nicholas Foulkes recalled the jury meeting in an article for the Patek Philippe Magazine on the occasion of the 20th anniversary of the first Annual Calendar’s launch: ‘The decision that year was reached unanimously and enthusiastically by all members, even though there were other outstanding candidates.’

The enthusiasm is easy to explain. Alongside its aesthetic and technical qualities, the model offered a truly useful, simple, yet entirely new complication. It is positioned between the simple calendar—which must be adjusted five times a year for months with fewer than 31 days—and the perpetual calendar, which requires no correction even in leap years but is significantly more expensive. If you would like to learn more about how the individual calendar mechanisms work, read our guide comparing the perpetual calendar, annual calendar, and complete calendar here.

Brilliantly simple – simply brilliant: The Reference 5035

This new mechanism only required adjustment once a year, at the end of February. It seemed so obvious, yet, for one thing, no one had come up with the idea until then. For another, it required an exceptional manufacture to both find a suitable technical solution and launch it at the right moment: a few years earlier, such a watch would hardly have been marketable. The patent granted for this mechanism in 1996 proves that timing in product sales is just as important as the product itself. The watch arrived at the perfect moment in the history of horology.

Retrospective: A History of Calendars

Naturally, the various methods of timekeeping and calendars seem very alien to modern cultures that no longer use them today.

Although the Romans introduced the Julian calendar in 46 BC, which simplified the calendar system, they apparently developed no specific mechanism to display it. The Greeks, by contrast, had already achieved astonishing technical breakthroughs significantly earlier. The famous Antikythera mechanism from the 2nd century BC was discovered around 1900 in the wreck of an ancient merchant ship and is the earliest known geared apparatus. It appears to have been a genuine calculating machine capable of determining the positions of certain stars and planets and predicting their eclipses. Among other features, the device possessed over 30 gears and several dials onto which instructions for use were engraved.

Even the Gauls were further ahead than the Romans—and not just when it came to Asterix’s magic potion. They observed the movements of celestial bodies and developed highly complex calendar systems. One example is the Coligny calendar from the 1st to 2nd century BC, which can be seen in the Gallo-Roman Museum in Lyon. The discovery was a sensation: the fragments, discovered in a field in 1897, turned out to be pieces of a bronze tablet measuring 148 x 90 cm. Written in a Celtic language but using Latin characters, the calendar represents a cycle of five years, each consisting of twelve months, mostly of 29 or 30 days. To harmonise the solar and lunar cycles, the Druidic astronomers had developed a highly complex system involving additional days and intercalary months.

“Unlike the mechanism discussed here, using the Coligny calendar required daily attention: the passing of the days was marked by a peg, which could be inserted into a hole in front of each line. It must have been very labourious, as it apparently functioned on a 30-year basis, suggesting that six similarly sized tablets – each covering five years – were needed.”

Gozitano, Fragment van de kalender, licensed under CC BY 4.0

Leap into the early modern era

This level of technical complexity remained unrivalled for over fifteen centuries and would only reappear with the astronomical clocks of the Middle Ages and the Renaissance. The miniaturised mechanisms of the 17th century were capable of displaying the time, date, day of the week, month, and moon phase on the dial of a pocket watch.

Towards the end of the 18th century, the perpetual calendar was developed, which accounts for leap years – a field in which Patek Philippe remains the undisputed leader, owing to its celebrated perpetual calendar wristwatches.

The Technical History: How the first Patek Philippe Annual Calendar was created

The Patek Philippe Annual Calendar is already regarded as an absolute classic within the manufacture’s collection; consequently, it is well worth tracing its history in meticulous detail.

It all began in 1991 with a diploma thesis initiated by Patek Philippe at the Geneva Engineering School. Such collaborations with schools and universities are a long-standing tradition at Patek Philippe and continue to this day, particularly in the field of micro-technology research in Neuchâtel. In this instance, the graduate was hired by Patek Philippe and still works for the manufacture today. His name is Cédric Fague, and thirty years later, he remains active in product development. From the outset, his brief was clear, having been set by the company’s then-head, Philippe Stern – father of the current president, Thierry Stern.

The objective was not to simplify the perpetual calendar – for example, by modifying the programme wheel that governs the 48 months of the four-year cycle between leap years. Rather, the aim was to take the simple calendar as a starting point and find an original, reliable, and robust solution that was efficient in both mechanical and financial terms. Specifically, the goal was to develop a mechanism that did not rely on the levers, rockers, and large return springs that drive classic perpetual calendars, but was based instead on rotary components.

To understand the reason for this radical option, we must once again look to the past: thirty years ago, it was far more difficult to produce finished shaped components than it is today, in an era where multi-axis CNC milling machines are industry standard.

To obtain perfectly smooth and large rockers, complex and costly adjustments and fine-tuning had to be carried out during final assembly back then. And it was precisely this problem that the developers aimed to circumvent by designing this mechanism using turned parts. The choice of turned parts would simplify production at acceptable costs while significantly increasing ease of use, durability, and suitability for everyday wear. The challenge remained to mechanically programme the transition from months with 30 days to the first of the following month five times a year.

The solution was a wheel with 31 teeth carrying a 12-month disc. A small feeler, whose shape earned it the nickname “Dolphin”, tracks this disc to manage the change to the following month on the 30th or 31st. While the prototypes improved from phase to phase, technicians and watchmakers worked together to simplify and reduce. One result was the decision to dispense with a return spring intended for the “Dolphin”. Theoretically, it was necessary; in practice, however, it proved to be dispensable, as its removal had no impact on the function.

Historical irony: the mechanism became simpler, yet it comprised more parts than the perpetual calendar!

By the end of the planning phase, despite the engineers’ efforts to simplify the design, the first annual calendar mechanism comprised more individual components than the perpetual calendar—and that remains true today. Consequently, the annual calendar with moon phases consists of nearly 330 parts, whereas a conventional perpetual calendar with a moon-phase display features only 275.

The explanation lies in the decision to use a system of wheels, all of which must be connected with pins and screws, rather than superimposed components. The advantages of the concept also outweighed its sole drawback: ideally, the movement should have been slim. However, in 1996, the engineers designed a 2 mm thick mechanism, which increased the total height of the first calibre to 5.2 mm, meaning the corresponding case also had to be taller.

Yet the market embraced this watch immediately, taking the bolder proportions of the debut model in its stride.

Perhaps it is also because the company’s internal requirement for the dial to be perfectly legible was fully met. The date display of a mechanism bearing the name Annual Calendar must be straightforward. And while perpetual calendars typically feature a pointer date, preference was given here to aperture displays and a more visually prominent date to guarantee the greatest possible ease of reading. Over time, the corresponding discs were enlarged and their positions adjusted so that the day and month indications became even clearer. A sophisticated optimisation of the aperture displays also compensated for the inherent differences in height between the discs.

A simple figure illustrates just how popular this complication is today: in 2026, there are around 160 references in Patek Philippe’s current collection, 17 of which are annual calendars alone – ranging from men’s to ladies’ watches, many in combination with other complicated mechanisms. And these are by no means watches intended only for those who cannot afford a perpetual calendar. But more on that later.

These are all the key Patek Philippe Annual Calendar models from 1996 to 2026

1996: Reference 5035 is immediately named ‘Watch of the Year’ in Switzerland

The Annual Calendar was launched in a round model featuring three sub-dials. The Ref. 5035 was an instant success and, as mentioned, received the ‘Watch of the Year 1996’ award. Equipped with the Calibre 315 S QA 24H (3 Hz), the Ref. 5035 had a case diameter of 37 mm. It was crafted in yellow, white, or rose gold, as well as platinum, featuring the Roman numerals that have since become iconic.

1998 – Reference 5036/1 with power reserve and moon phase and a new metal bracelet

The movement was then optimised with a power reserve indicator and a highly precise moon-phase display, which replaced the 24-hour scale on the Ref. 5036/1; diameter: 37 mm. At the same time, this was the first model to feature a gold bracelet in 1998.

The power reserve indicator is positioned at 12 o’clock and the moon phase display above the date window at 6 o’clock. As with the original annual calendar, the month and day of the week are displayed on two subsidiary dials. On the dial, the hours are marked by Roman numerals with gold appliqués, which, like the feuille hands, glow in the dark. The use of the numeral IV instead of the IIII traditionally used by watchmakers for the 4 o’clock marker is rather unusual.

All three complications in the watch are driven by winding mechanisms; the automatic Calibre 315, which still bears the Hallmark of Geneva, comprises 61 individual components that together form the separate gear trains for the movement, the annual calendar, the moon phase display and the power reserve indicator. The movement can be admired through a sapphire crystal case back. The annual calendar can be set on 1 March each year using a pusher. Available in yellow, white and rose gold, this model was the first to feature a matching metal bracelet created exclusively for the annual calendar.

1999, the second platinum model, Ref. 5056

In 1999, a year later, this watch was released as Ref. 5056, the second platinum model featuring an annual calendar on a leather strap. Thierry Stern, then the new president of Patek Philippe, was responsible for the development of the Ref. 5056 in a 37-mm platinum case. The slate-grey dial remains highly contemporary to this day.

2001: A sought-after Tiffany design

The 36 mm Ref. 5150 was launched to mark the 150th anniversary of the partnership with Tiffany & Co., hence the ‘T’ at 12 o’clock. The first annual calendar with windows displaying the day and month – the month being indicated by a numeral, which is unusual – was produced in limited editions of 150 pieces each in yellow, white and rose gold.

2003: A special award for the German jeweller Wempe

Patek Philippe has enjoyed a long-standing relationship with Wempe. The Hamburg-based jeweller has stocked the Geneva-based brand since 1929, and the Stern and Wempe families maintain a friendly relationship. To mark the 125th anniversary of the House of Wempe in 2003, the 36.5 mm Ref. 5125 was launched, reminiscent of the vintage references 3448 and 3450. Only 475 pieces were produced: 125 each in yellow, white and rose gold, and 100 in platinum. It will be interesting to see what Wempe and Patek will come up with together in two years’ time to mark the company’s 150th anniversary.

2004: Gondolo Calendario Ref. 5135, the first annual calendar watch featuring the Calibre 324 QA movement

In fact, since its launch, there has hardly been a year in which the annual calendar has not featured an exciting new development: in 2004, the function was once again in the spotlight with the launch of the Gondolo Calendario Ref. 5135. It impresses with its familiar tonneau case, as well as the brand-new automatic movement and, for the first time, arched day, date and month windows. The 38 × 51 mm Gondolo Calendario Ref. 5135 was not only the first annual calendar featuring the Calibre 324 QA (4 Hz) movement and the first in the historic tonneau case, but above all the first model in the regular collection with the striking three-window display. Today, the men’s Gondolo is also rare because the last classic men’s references were discontinued in 2019 and the model is now part of Patek’s collection as a ladies’ watch.

2005–2015: The first highly complex ladies’ watches with an annual calendar

The Ref. 4936

In response to the growing success of the annual calendar, Patek Philippe unveiled its first ladies’ model in 2005. The Ref. 4936, featuring a mother-of-pearl dial and diamonds, was followed the following year by a haute joaillerie model: the Ref. 4937 in white gold, set with 472 diamonds. The 37 mm Ref. 4936 was also one of Patek Philippe’s very first complicated ladies’ watches at the time. It featured a black Tahitian mother-of-pearl dial, whilst the yellow gold model and, later, the rose gold version featured white mother-of-pearl dials.

2005: From 37 mm to 39 mm – the Ref. 5146

In the same year, Patek Philippe also delighted male enthusiasts with the launch of a new basic model featuring a slightly larger diameter (39 mm instead of 37 mm) and finely crafted dials. This model, Ref. 5146, in yellow, rose or white gold or platinum with an alligator leather strap, was joined by the Ref. 5146/1, which was worn on yellow or white gold bracelets. The following year, the company launched an elegant, jewel-set white gold version, Ref. 5147, with a midnight blue lacquered dial framed by 62 diamonds.

2005: ‘Advanced Research’ makes its world debut in the 5250 model with an annual calendar

The mechanism also takes pride of place in pioneering models such as the first three limited editions of the Patek Philippe “Advanced Research” concept: the Ref. 5250 from 2005, which is equipped with the first silicon escape wheel in the manufacture’s history, and of which only 100 examples were produced in white gold. This was followed in 2006 by the Ref. 5350 in rose gold, whose movement featured the Patek Philippe silicon escape wheel and the Spiromax balance spring made of Silinvar; 300 examples were produced.

Two years later, in 2008, the Reference 5450 Annual Calendar was presented, limited to 300 pieces and marking the first time an Advanced Research watch was crafted in platinum. This model featured not only the Gyromax balance with a Spiromax spring but also the new Pulsomax escapement and a redesigned escape wheel, complemented by a silicon pallet fork. All of this is visible through the sapphire crystal caseback, which charmingly features an integrated Cyclops magnifier over the escapement group—similar to those found over the date window on well-known Rolex Oyster Date models, only significantly larger.

The Reference 5450P is particularly striking for its characteristic salmon-coloured “Salmon” dial. As the first Advanced Research model in a platinum case, it naturally stands out due to the small diamond set between the lugs at six o’clock, which distinguishes all platinum watches from Patek Philippe. Fun Fact: As the final Annual Calendar model in the collection, it was also the last model in the Advanced Research series to be awarded the Geneva Seal, as Patek Philippe transitioned all its timepieces to the new in-house Patek Philippe Seal in 2009.

2006: Annual calendar in a Calatrava case, Ref. 5396

Things are moving at a rapid pace. In 2006, the movement was fitted into one of Patek’s most famous models, the Calatrava. The 38.5 mm Ref. 5396 was launched in rose gold and then in white gold. The earlier models featured sector dials with a vintage look, whilst later versions boasted the classic Calatrava dial with applied baton hour markers.

2006: Perhaps the most historically significant model – the first annual calendar chronograph, Ref. 5960P

In 2006, the annual calendar was incorporated into the technically outstanding calibre of the Annual Calendar Chronograph Ref. 5960P – the first automatic chronograph to be developed and manufactured entirely in-house. When the Annual Calendar Chronograph Ref. 5960 was launched in 2006, it immediately captivated collectors with its rare combination of complexity and practicality for everyday use. “Aficionados have been waiting a long time for a new Patek Philippe chronograph,” said the company president, announcing the debut of the Ref. 5960.

To understand the immense significance of Ref. 5960, one must look back to 1998, the year in which the Ref. 5070 chronograph, featuring two sub-dials, made its debut. This model heralded Patek Philippe’s return to chronograph manufacturing.

Credit © Christies

Thanks to its historically inspired design and generous dimensions, the 42 mm Ref. 5070 has rightly become popular with collectors. An issue of Patek Philippe Magazine states: “For Patek Philippe, however, the model was a compromise in that it was fitted with the Calibre CH 27-70, a comprehensively revised and finished version of the Nouvelle Lémania ébauche. This hand-wound base calibre from the early 1940s, although universally popular, was showing its age. Furthermore, Philippe Stern, as president, had decided to make the manufacture self-sufficient and to produce all calibres in-house rather than relying on external suppliers.”

Credit © Christies

He was right. We got a taste of this in 2005, when the world’s thinnest split-seconds chronograph movement, the CHR 27-525 PS, was launched. But it was only with the CH 28-520 IRM QA 24H, which ticked away a year later in the Ref. 5960 with an annual calendar, that Mr Stern’s bold vision became clear.

The chronograph hand is also used to indicate the running seconds

The movement featured a flyback function based on the classic column wheel for controlling start/stop commands, but with one improvement: power was transmitted from the seconds wheel to the chronograph wheel not via a rocker arm with a clutch wheel, but via a disc clutch, in which two clutch discs engage or disengage to transmit or interrupt the power.

Furthermore, thanks to the use of the seconds wheel, the movement did not require the traditional chronograph gear train, which should not be kept running continuously to prevent wear and tear. The new calibre allowed the chronograph hand to run continuously, meaning it could be used as a running seconds hand, whilst the flyback function enabled an immediate switch from the running seconds to the chronograph function.

These technical advances were brought to life by an equally innovative chronograph display: a single ‘porthole’ counter at 6 o’clock combined the functions usually handled by separate displays into a single totaliser: A long red hand counted the minutes on two outer concentric scales: from zero to 30 in red and from 30 to 60 in blue. A shorter blue hand allowed events to be recorded on an inner scale over a period of 60 minutes up to 12 hours.

This sub-dial also featured a small window that alternated between white and dark blue to indicate day and night – and linked to the upper half of the dial, where the familiar three windows between 10 o’clock and 2 o’clock displayed the day of the week, date and month. The day/night indicator is adjustable via three pushers on the left side of the case and helped to update the calendar after a period of inactivity. The hour chronograph function alone makes the Ref. 5960 a milestone on the path to the modern Patek Philippe manufacture; the combination with the famous annual calendar mechanism makes the model historic.

Another aspect of its significance becomes apparent when one compares the Ref. 5960 with chronographs featuring a perpetual calendar and manual winding, such as the legendary Ref. 1518 and Ref. 2499. With the Ref. 5960, the Manufacture offered, for the first time, a modern, user-friendly and more practical combination of calendar and chronograph functions. Given its emblematic contribution to the Patek Philippe canon, it was fitting that the Ref. 5960 was initially available only in the finest of all metals: platinum. This was followed in 2011 by the platinum chronograph annual calendar Ref. 5961P, with a diameter of 40.5 millimetres, a bezel set with 36 baguette-cut diamonds and baguette-cut diamonds as hour markers.

The 5960P from 2006 was replaced in 2015 by the Ref. 5905, featuring a larger 42-millimetre platinum case, a dial with concentric circles and square chronograph pushers. The first steel version of this model is the Ref. 5905/1A from 2021, which is still available today and features a dark green dial. It is perhaps the most appealing version of a sporty Patek Philippe currently available and certainly did not appear by chance in the same year that the Nautilus was discontinued.

2006–2015: The first minute repeater with an annual calendar – the Gondolo Ref. 5033

Highly complex movements are making a second appearance in the collection: the 38 × 51 mm Ref. 5033, featuring a tonneau-shaped case and a minute repeater, was the first annual calendar watch with a Grande Complication. This model has been in production since 2006 and has so far been available in four versions: in platinum with a white dial (Ref. 5033P – 010 from 2006 to 2010) and in platinum with a black dial (Ref. 5033P-12), which was only available for one year from 2010 to 2011. In 2011, the Ref. 5033/100P – 010 was fitted with a bezel set with baguette diamonds and a white dial, whilst the Ref. 5033/100P – 001 from 2011–2015 also featured a bezel set with baguette diamonds.

According to Phillips auction house, however, the watch’s history goes back even further: Logan Baker writes on the auction of one of these rare pieces: “The Gondolo Minute Repeater Annual Calendar Ref. 5033 was first unveiled in 2002 in a limited edition of just ten watches. Nine were crafted in platinum, whilst a single piece was made in titanium. Patek Philippe, however, quickly decided to go beyond these first ten pieces and began producing a small number of additional examples each year, which were offered exclusively to their best clients. The exact total production figure is unknown, but it is estimated that around 80 different examples of the Ref. 5033 were produced over a period of ten years.” A very readable article, by the way.

Credit © Phillips

2010: The new white gold case is increased to 40 millimetres

The 40 mm Ref. 5205G in white gold – also available in rose gold from 2013 onwards – features a new case with skeletonised lugs, large gold applied baton hands and a two-tone dial.

2011: Patek Philippe Reference 5235 Annual Calendar Regulator

This model stands out in the entire history of Patek: with the Annual Calendar Reference 5235 Regulator, Patek Philippe introduced a completely new watch model that had never before featured in the manufacture’s collection. For the first time, a Patek Philippe wristwatch featured a distinctive regulator dial, characterised by a large minute hand in the centre, a small hour dial at 12 o’clock and a small seconds dial at 6 o’clock.

The model was powered by the new Calibre 31-260 REG, the first ultra-thin Patek Philippe automatic movement with a micro-rotor to feature a small seconds display at 6 o’clock. It was also the first entirely new base movement designed to incorporate Silinvar components: the escape wheel and anchor with Pulsomax escapement, as well as the Spiromax balance spring, are made from the innovative silicon derivative. The new wristwatch is rounded off by the annual calendar with window displays. The Silinvar components are completely non-magnetic, extremely shock-resistant, corrosion-free and do not require oiling.

A clear commitment to precision timekeeping

It is a clear commitment to the philosophy that a Patek Philippe should, above all, be an accurate and reliable timepiece.

The dial is, of course, a tribute to the precision timepieces that kept accurate time in observatories for over 200 years, until they were replaced by quartz and radio-controlled time standards. To ensure that watchmakers could always have an unobstructed view of the seconds hand when adjusting their watches, the hour display was positioned in such a way that its hand could not partially obscure the seconds dial for several hours each day. The President of Patek also used such clocks to regulate his wristwatches: one of these grandfather clocks was built as a regulator by Patek Philippe & Co at the beginning of the 20th century and is said to stand in the office of Honorary President Philippe Stern.

However, this entirely new regulating mechanism was not enough for the Patek Philippe engineers. Consequently, the finishing gear train – the wheels and pinions between the mainspring barrel and the escape wheel – was also completely redesigned. The profiles of the wheel teeth and pinion wings were analysed in detail, recalculated and individually designed for all wheels and pinions (minute wheel, small-wheel, second wheel with associated pinions). These new profiles improve the engagement of the wheel teeth and pinion flanges, reduce friction, increase tolerance for varying centre distances and enhance the efficiency of energy transmission from the mainspring barrel to the escape wheel. The result is a significant increase in efficiency whilst simultaneously reducing wear.

The exceptional balance wheel frequency of 3.2 hertz

The innovative technologies of the new Regulator calibre 31-260 REG QA, designed to enhance efficiency and isochronism, have far-reaching implications: Whilst the automatic calibre 240 beats at 21,600 vibrations per hour, the frequency of the new movement has been increased by almost 10 per cent to 23,040 vph or 3.2 Hz, whilst simultaneously increasing the power reserve. A higher frequency, in turn, makes it easier to adjust the movement’s accuracy to meet the specifications of the then-new Patek Philippe Seal (-3/+2 seconds per 24 hours). This had been introduced two years earlier, in June 2009.

The fourth innovation was an extra-long mainspring for a particularly long power reserve. Thanks to the careful management of the driving energy, it was also possible to use a longer mainspring. The new Calibre 31-260 REG QA therefore achieves a power reserve of 60 hours despite its increased frequency and with just a single barrel (Calibre 240: 48 hours). The longer mainspring also has the advantage of a flatter torque curve, ensuring a stable amplitude and consistent timekeeping for the majority of the power reserve. The result is greater timekeeping accuracy over a longer period – the ability to take the watch off for a whole weekend without having to reset the time and calendar on Monday speaks to the watch’s practicality for everyday use.

Automatic and manual winding in one watch

To ensure the new annual calendar regulator has the longest possible service life and long-term reliability, further innovations were introduced: like all Patek Philippe automatic movements, the Calibre 31-260 REG QA can also be wound manually. However, the manual winding mechanism is automatically disengaged whenever the automatic winding mechanism is in operation. This increases winding efficiency and reduces wear. Furthermore, the 22-carat gold micro-rotor set into the mainplate is 0.3 mm thicker than that of the Calibre 240, which increases its mass. Compared to the Calibre 240, the new Calibre 31-260 REG QA had a frequency that was almost 10 per cent higher and a power reserve that was 25 per cent greater, which corresponds to an overall increase in efficiency of around 30 per cent.

In 2019, this watch was succeeded by a gold version, reference 5235/50R, which remains the only Patek Philippe model with a regulator dial in the collection to this day. Six years ago, the Manufacture gave this model a new look. It combined a rose gold case with a vertically satin-finished dial in graphite grey and ebony black, adorned with white details. This striking design is complemented by rose gold baton hands, which in turn are reminiscent of the old regulator clocks. Three railway-track scales along the edge of the dial and around the subsidiary dials for the hours and seconds emphasise its timeless elegance.

2010: Ref. 5726 – The first Nautilus with an annual calendar

Sixteen years ago, Patek Philippe combined sporty style with sophisticated technology for the first time in the Nautilus collection with the Ref. 5726. The famous Gerald Genta design now featured, for the first time, an annual calendar, a moon phase display and a 24-hour display; however, the dial was grey and it was only available on a leather strap: This stainless steel Ref. 5726A was joined in 2012 by the first model with a stainless steel bracelet, the 40.5-millimetre Ref. 5726, also with a grey dial.

Two years before the steel model was discontinued (including the dark green and Tiffany dial variants), the Geneva-based manufacturer finally launched the much-coveted Reference 5726/1A in 2019, featuring a stainless steel bracelet – and, like the first Nautilus from 1976, an elegant blue dial. It will be interesting to see whether this watch makes a comeback to mark the 50th anniversary of the Nautilus and the 30th anniversary of the annual calendar!

An important detail: on the first Nautilus model with an annual calendar, the horizontal embossed pattern was accentuated by a subtle black gradient starting at the edge of the dial. Applied hour markers and hands in white gold with a luminescent coating indicate the hours and minutes, whilst a central hand indicates the seconds.

2014: Finally, an annual calendar watch with a stainless steel case and stainless steel bracelet: the Ref. 5960/1A

For the author, this model is a real phenomenon, as it is not only one of the most striking designs in the entire collection, but also the first chronograph to be produced in two versions in stainless steel: the Ref. 5960/1A with automatic winding also has a diameter of 40.5 millimetres. It was the first annual calendar chronograph with a stainless steel case and bracelet.

2016: Anniversary model in rose and white gold: Ref. 5396

Launched to mark the 20th anniversary of the Annual Calendar, the Ref. 5396 in white gold has a diameter of 38.5 millimetres, features a new anthracite-coloured sunburst dial and is fitted with large applied Breguet numerals. It is also available in a rose gold case with an opaline silver-coloured dial. In both cases, the case shape is reminiscent of the iconic Calatrava 96. Both versions display the date and month in a linear double window.

2022: Travel Time Annual Calendar, Reference 5326G-001

The year 2022 can also be described as a milestone for Patek Philippe and the annual calendar mechanism: two extremely useful complications are combined for the first time in a Patek. The Manufacture has combined two of its most important patented complications in a single watch: the annual calendar and the Travel Time system for displaying a second time zone. The result Ref. 5326G-001 is a travel watch whose date display is synchronised with the local time. When the time zone is adjusted, the date is automatically updated. For the new automatic movement, Calibre 31-260 PS QA LU FUS 24H, which is protected by eight patents, the Manufacture even created a new Calatrava case. The sides feature the characteristic guilloché ‘Clous de Paris’ design. The vintage-style dial is reminiscent of the look of old cameras.

Flashback: The travel-time function was introduced a year after the annual calendar

A year after the annual calendar, in 1997, came the Travel Time mechanism. It features a clutch mechanism based on a Patek Philippe patent from 1959! Its ingenious system, featuring a second hour hand, displays the time in a second time zone from the centre. Two pushers on the left side of the case advance and retreat the time zone in one-hour increments without affecting the movement’s operation.

Combining the annual calendar with the travel-time function presented the developers with technical challenges. Not only did both mechanisms have to be housed within the same watch case, but the displayed date also had to be synchronised with the local time. At the same time, both mechanisms must move forwards or backwards simultaneously when the time zone is changed. In the new Calibre 31-260 PS QA LU FUS 24H, the Travel Time function therefore controls the annual calendar. It is the local time hour wheel that drives the calendar. A principle from the World Time Minute Repeater Reference 5531 (2017) was applied here: during the first minute repeater strike, which signals the respective local time, the world time mechanism controls the minute repeater.

The travel time function has also been revised for the annual calendar

Patek Philippe has also revised the Travel Time function for the new 5326G-001. Whilst the basic principle of two central hour hands remains the same – a solid hand for local time and a hollowed-out hand for home time – the designers have replaced the time zone pushers on the left side of the case with a setting mechanism via the winding stem. It can be set to three positions and made its debut in 2021 in the Aquanaut Luce Travel Time reference 5269/200R-001. The wearer simply needs to pull the crown out to the middle position – turning it clockwise to advance, and anti-clockwise to delay – to adjust the local time hour hand in one-hour increments. According to Patek Philippe Magazine, this crown adjustment system was developed for aesthetic reasons. Patek Philippe apparently wanted a simple Calatrava-style design combined with a distinctive decoration on the sides of the case. The time in the home time zone is set by turning the crown to its outermost position.

Another new feature: an annual calendar with a shorter ad rotation cycle

Is there really nothing to criticise in the thirty-year history of the annual calendar? Well, of course there is: in all previous annual calendars, the date change at midnight has taken around 90 minutes. This is a problem for a watch with a Travel Time function: it could cause a date discrepancy if the time zone is adjusted during this window. To ensure the wearer has the correct date display, Patek Philippe’s engineers have reduced the display changeover time for the annual calendar discs by a factor of five to approximately 18 minutes. It will be interesting to see whether, following the launch of the instantaneous Day-Date reference 5328G-001, Patek will succeed in transferring this technology to the annual calendar as well. Although a spontaneously jumping date requires a huge amount of energy, it would be of practical use.

Eight new patents ensure greater reliability and easier operation

But back to the Travel Time annual calendar: to optimise the efficiency, reliability and ease of use of the Calibre 31-260 PS QA LU FUS 24H, the designers have developed further innovations that have resulted in eight patents: For example, energy consumption and wear on components responsible for the transition from the 30th to the 1st and from the 1st to the 30th were reduced, without throwing the date out of sync when adjusting the time zone. Similarly, misalignments and double jumps in the displays have been eliminated, and damage to movement components has been prevented when the moon phase, month or day of the week is corrected within a time window that is actually officially and expressly discouraged. These refinements make the watch even better.

A dial with a vintage look

The most striking feature of the 5326G-001 is its vintage-style dial. It was entirely crafted by Cadrans Flückiger in Saint-Imier. This specialist has been part of Patek since 2004. The dial is anthracite in colour with a subtle black gradient towards the outer edge and features a slightly grained texture reminiscent of the casings of old cameras. The time is read via white gold Arabic numeral hour markers with a beige luminescent coating. The local time hours and minutes are indicated by Seringue hands in luminescent white gold. A skeletonised Seringue hand indicates the home time hours.

2023: The first Aquanaut Luce Annual Calendar, reference 5261R-001

It was only three years ago that the sporty yet elegant Aquanaut Luce ladies’ watch Ref. 5261R-001 was fitted with this new, practical and user-friendly complication. With its blue-grey dial and strap, this rose gold model expanded the range of Patek complications for women.

Launched in 2004, the Aquanaut Luce collection has, until now, been the feminine interpretation of the Aquanaut wristwatches launched in 1997. For several years now, Patek Philippe has been expanding the sporty Aquanaut Luce range for women with various complications. Housed in a 39.9 mm diameter case, the automatic Calibre 26-330 S QA LU features a central rotor and an annual calendar module with an annual calendar and moon phases. A distinctive feature: the annual calendar module is positioned upside down. The date window is positioned at 6 o’clock, the day-of-the-week indicator at 3 o’clock and the month indicator at 9 o’clock. The architecture of the movement follows that of the base calibre 26-330, which was launched in 2019 with the Calatrava weekly calendar, reference 5212A-001.

A bestseller of historical significance

On its 30th anniversary, the annual calendar has long been one of Patek Philippe’s bestsellers, and it is still based on the same mechanism, even long after the patent has expired. You don’t need to be a prophet to predict, based on this, that the function still has a bright future ahead of it across the entire watch industry. Moreover, major manufacturers are naturally getting in on the act today: since 2012, the Saros annual calendar has been available in Rolex’s Sky-Dweller with the month display via 12 dial apertures, and since 2015 also as a Co-Axial calibre model in Omega’s Globemaster Annual Calendar. IWC followed suit with the Portugieser Annual Calendar, even adopting Patek’s reference numbering: Coincidence or not, the reference numbers are identical to Patek’s first model, the 5035 (though the calibre at IWC is called 52850). Incidentally, German manufacturer A. Lange & Söhne has had such a function in its range since 2010 with the Saxonia Annual Calendar, featuring the automatic in-house calibre L085.1 and, of course, a large date.

A Calatrava Pilot with an annual calendar? Or perhaps a Cubitus?

We don’t want to speculate too much about what the future holds for this Epoche model. Which model might be next? It would make just as much sense in the Calatrava Pilot range introduced by Thierry Stern as it would in the Cubitus range. But for 2026, other things took priority:

At the start of the watch year at Watches and Wonders 2026, things were surprisingly quiet around this complication: the 50th anniversary of the Nautilus and the new Celestial were the stars of the show, alongside two newly unveiled annual calendar models: The 4946G-001 Annual Calendar Moon Phase is intended as a design statement: the design, featuring a polished 38 mm white gold case, has been combined for the first time with a blue-grey dial, whose vertical and horizontal satin finish is reminiscent of raw shantung silk fabrics. The time is indicated by leaf-shaped white gold hands with a white luminescent coating, which glide over another distinctive feature of this new model: monoblock hour markers made of white luminescent material, ensuring optimal legibility and high contrast. A strap in blue-grey calfskin with a ‘jeans’ motif and contrasting white stitching, secured by a white gold clasp, emphasises the decidedly contemporary look of this model. The sapphire crystal case back, offering a view of the 26-330 S QA LU automatic movement, makes this watch an absolute eye-catcher from both sides.

The second new model, the 5396R-016 Annual Calendar Moon Phase, by contrast, has a distinctly more classic look: the Calatrava design of the 38.5 mm rose gold case has been combined with a sand-beige ‘sunburst’ dial. With its dual window displaying the day of the week and month at 12 o’clock, a date display at 6 o’clock, and a sub-dial for the 24-hour display including moon phases, it joins the models in the Calatrava range first introduced in 2006, thereby celebrating the 20th anniversary of this watch collection. The faceted Dauphine hands are crafted from rose gold.

Perhaps one final tip for collectors of sought-after steel models from Patek Philippe: in addition to the coveted platinum references mentioned above, the Nautilus models and some ladies’ watches were also produced with steel cases. And it is, of course, no coincidence that the successors to the steel Nautilus, specifically the annual calendar models, are still in production today: With reference 5726/1A-014 (featuring a steel bracelet and a dark blue gradient dial) and as ref. 5726/A-001, the model with a grey dial and leather strap has been in the range continuously for 16 years since its initial launch. Alongside the Nautilus models, the steel reference with a steel bracelet and white dial certainly stands out, as does the annual calendar chronograph Ref. 5960/1A from 2014 and its currently still available successor with a green dial, which was introduced in 2021.

The British historian and watch expert Nicholas Foulkes has written extensively about Patek’s annual calendar. I would like to conclude with a quote from him, who also provided the editorial commentary for the first annual calendar: “It was to become known as a useful complication and play a major part in making the Manufacture what it is today. One should not forget what it was all about with the Ref. 5035.” There is nothing more to add to that. Without the Patek Philippe annual calendar, Patek Philippe would not be where the manufacture stands today: at the pinnacle of mechanical watchmaking.

---

patek.com