The Superlative Watch Co. useful-complication reference
Patek Philippe Annual Calendar Buying Guide
Understand the patented 1996 mechanism, compare Annual Calendar and perpetual-calendar ownership, decode the principal Patek Philippe calibres, and move from a reference family to an exact available watch.
Direct answer
What is a Patek Philippe Annual Calendar?
It is a mechanical calendar that distinguishes 30-day months from 31-day months and advances the day, date and month accordingly. It requires one manual correction each year, at the end of February. Patek Philippe invented and patented the mechanism and introduced it in 1996 as a practical bridge between a simple calendar and a perpetual calendar.
The 1996 mechanism
Why the Annual Calendar changed practical high watchmaking
A conventional date watch assumes every month has 31 days, so its owner corrects the display after every shorter month. Patek Philippe's Annual Calendar adds a mechanical program for the alternating lengths of ordinary months.
The mechanism recognizes whether the current month has 30 or 31 days and makes the correct transition without owner intervention. February is the exception: its 28 or 29 days require information about the leap-year cycle that the Annual Calendar does not calculate. The owner therefore corrects the display once, after February, and the mechanism resumes its month-length program for the rest of the year.
This is why “annual” describes the correction interval, not the duration of the calendar. If the watch remains running and correctly set, its calendar is mechanically useful every day; the annual intervention is simply the price of a less complex architecture than a perpetual calendar.
Important distinction: moon phases, chronographs, Travel Time and regulator displays can be added to an Annual Calendar, but they do not change the underlying February correction requirement.
Calendar hierarchy
Annual Calendar vs. perpetual calendar
Both are complete calendars, but they solve different ownership problems. The Annual Calendar trades one predictable yearly correction for a generally simpler mechanism and a broad range of display, case and complication choices.
| Question | Annual Calendar | Perpetual calendar | Buyer implication |
|---|---|---|---|
| Month lengths | Recognizes 30- and 31-day months | Recognizes 30- and 31-day months plus February and the leap-year cycle | Both automate ordinary month-end changes. |
| Routine correction | Once each year, after February | No routine calendar correction while continuously running, apart from exceptional century handling | The practical difference appears once a year. |
| Patek classification | Complications | Grand Complications | Do not treat Annual Calendar and perpetual calendar as interchangeable labels. |
| Typical indications | Day, date and month; many references add moon phases or 24-hour indication | Day, date, month and leap-year cycle; layouts vary | Compare the exact dial, not the category name alone. |
| Ownership profile | High utility with one planned annual setting event | Maximum calendar autonomy with more complex architecture | Choose on wear, display and service priorities—not prestige shorthand. |
A stopped watch must still be reset. “Perpetual” describes the calendar program, not an unlimited power reserve.
Commercial reference map
Ten Patek Philippe Annual Calendar references to understand
The useful way to compare these watches is by display architecture and movement family. The exact suffix identifies the metal, dial and bracelet or strap execution; the calibre identifies what the mechanism actually does.
| Reference | Collection / character | Calendar and added function | Calibre | Exact watch |
|---|---|---|---|---|
| 4947/1A-001 | Complications; 38 mm steel bracelet | Day/month by hands, date aperture, moon phases | 26-330 S QA LU | View watch |
| 5205G-013 | Complications; white gold, blue gradient dial | Day/date/month apertures, moon phases, 24-hour display | 26-330 S QA LU 24H | View watch |
| 5205R-011 | Complications; rose gold, olive dial | Day/date/month apertures, moon phases, 24-hour display | 26-330 S QA LU 24H | View watch |
| 5396R-016 | Complications; classical rose-gold case | Day/month apertures, date aperture, moon phases, 24-hour display | 26-330 S QA LU 24H | View watch |
| 5235/50R-001 | Complications; regulator-style dial | Annual Calendar with separated hours, seconds and central minutes | 31-260 REG QA | View watch |
| 5326G-001 | Complications; white-gold travel watch | Annual Calendar, two time zones, local/home day-night, moon phases | 31-260 PS QA LU FUS 24H | View watch |
| 5905/1A-001 | Complications; steel integrated bracelet | Flyback chronograph, 60-minute counter, Annual Calendar | CH 28-520 QA 24H | View watch |
| 5905R-010 | Complications; rose gold on strap | Flyback chronograph, 60-minute counter, Annual Calendar | CH 28-520 QA 24H | View watch |
| 5726/1A-014 | Nautilus; steel bracelet | Day/date/month apertures, moon phases, 24-hour display | 26-330 S QA LU 24H | View watch |
| 5261R-001 | Aquanaut; rose gold, composite strap | Day/month by hands, date aperture, moon phases | 26-330 S QA LU | View watch |
Movement decoder
Five Annual Calendar calibres—and why they are not substitutes
Patek Philippe's calibre names are functional maps. QA denotes the Annual Calendar architecture; LU denotes moon phases; 24H adds a 24-hour or day/night indication; FUS identifies a dual-time mechanism; PS identifies subsidiary seconds; CH identifies a chronograph; REG identifies the regulator display.
Day and month by hands, date in an aperture, moon phases and sweep seconds. Used by the 4947/1A-001 and 5261R-001.
View a watch with this calibre
Annual Calendar, moon phases, 24-hour indication and sweep seconds. It supports the 5205, 5396 and 5726 families.
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Self-winding flyback chronograph with central seconds, 60-minute counter and Annual Calendar indications arranged along the dial arc.
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Links the calendar to local time while adding home time, separate day/night indications, moon phases and small seconds in Ref. 5326G-001.
View a watch with this calibre
Separates the time display into central minutes with hour and seconds subdials, then integrates day, date and month apertures.
View a watch with this calibreMovement imagery is illustrative. The exact calibre suffix, case execution and production-era specification must be verified on the individual product page and official reference documentation.
Exact watch listings
Available Patek Philippe Annual Calendar watches
Each photograph links to the individual watch listing. Previously sold watches may remain available to view as reference examples; check the listing for current availability.
Steel · Complications
4947/1A-001
26-330 S QA LU
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VIEW WATCHView this exact reference — 5205G-013
White gold · Complications
5205G-013
26-330 S QA LU 24H
View exact watch
VIEW WATCHView this exact reference — 5205R-011
Rose gold · Complications
5205R-011
26-330 S QA LU 24H
View exact watch
VIEW WATCHView this exact reference — 5396R-016
Rose gold · Complications
5396R-016
26-330 S QA LU 24H
View exact watch
VIEW WATCHView this exact reference — 5235/50R-001
Regulator · Complications
5235/50R-001
31-260 REG QA
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VIEW WATCHView this exact reference — 5326G-001
Travel Time · Complications
5326G-001
31-260 PS QA LU FUS 24H
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VIEW WATCHView this exact reference — 5905/1A-001
Steel · Flyback chronograph
5905/1A-001
CH 28-520 QA 24H
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VIEW WATCHView this exact reference — 5905R-010
Rose gold · Flyback chronograph
5905R-010
CH 28-520 QA 24H
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VIEW WATCHView this exact reference — 5726/1A-014
Steel · Nautilus
5726/1A-014
26-330 S QA LU 24H
View exact watch
VIEW WATCHView this exact reference — 5261R-001
Rose gold · Aquanaut
5261R-001
26-330 S QA LU
View exact watch
Decision framework
Choose the display and use case before the metal
| Priority | Start with | Why | Then verify |
|---|---|---|---|
| Classic dress proportions | 4947/1A, 5205 or 5396 | Clear calendar identities without an added timing or travel mechanism | Case diameter, lug profile, aperture vs. hand display and strap/bracelet |
| Sport bracelet | 5726/1A or 5905/1A | Nautilus architecture or a steel flyback-chronograph execution | Bracelet fit, case finish, thickness and exact inventory condition |
| Casual sport format | 5261R | Aquanaut case, composite strap and inverted calendar layout | Strap sizing, clasp, rose-gold condition and display orientation |
| Travel | 5326G | Annual Calendar synchronized with Travel Time functionality | Local/home indications, setting sequence and complete accessory set |
| Timing | 5905 | Flyback chronograph and Annual Calendar in one automatic calibre | Chronograph reset, calendar transition, thickness and service evidence |
| Unconventional display | 5235/50R | Regulator layout separates hours, minutes and seconds | Dial readability, case condition and comfort with the display logic |
Exact-watch due diligence
Setting, service and transaction controls
The Annual Calendar is designed for daily usefulness, but correct operation still depends on the exact calibre, corrector layout and documented setting procedure.
Do not quick-set by guesswork. If a watch has stopped, follow the exact reference instructions before using any recessed corrector. Calendar damage can result from correction at the wrong time or in the wrong sequence.
Search-led answers
Patek Philippe Annual Calendar FAQs
What is a Patek Philippe Annual Calendar?
A Patek Philippe Annual Calendar is a mechanical calendar that distinguishes 30-day months from 31-day months and automatically advances the day, date and month. It needs one manual correction each year, at the end of February.
How often does a Patek Philippe Annual Calendar need correction?
Once per year, after February. The mechanism handles ordinary 30-day and 31-day months, but it does not calculate February's 28 or 29 days.
What is the difference between an Annual Calendar and a perpetual calendar?
An Annual Calendar recognizes 30-day and 31-day months but needs one correction after February. A perpetual calendar also tracks February and the leap-year cycle, so it does not need that routine annual correction while it remains running.
Who invented the Annual Calendar watch?
Patek Philippe invented and patented the Annual Calendar mechanism and introduced it in 1996 as a useful complication requiring only one correction per year.
Is a Patek Philippe Annual Calendar a Grand Complication?
Normally no. Patek Philippe places Annual Calendar watches in its Complications collection. Its perpetual calendars are classified as Grand Complications.
Which movement powers the Patek Philippe 5205, 5396 and 5726?
The current references covered here use variants of calibre 26-330 S QA LU 24H, combining the Annual Calendar with moon phases, a 24-hour indication and sweep seconds. Always verify the exact reference and production-era specification.
What complications does the Patek Philippe 5905 combine?
The 5905 combines a self-winding flyback chronograph with an Annual Calendar. Its CH 28-520 QA 24H calibre adds central chronograph seconds, a 60-minute counter and calendar indications arranged along the dial.
What is special about the Patek Philippe 5326G-001?
The 5326G-001 combines the Annual Calendar with Patek Philippe's Travel Time system. Its calendar follows local time and is joined by home time, separate day/night indications, moon phases and small seconds.
What is special about the Patek Philippe 5235/50R-001?
The 5235/50R-001 uses a regulator-style display with central minutes and separate hour and seconds subdials, while day, date and month appear in apertures. It is powered by calibre 31-260 REG QA.
Which Patek Philippe Annual Calendar is the best place to start?
There is no universal best reference. Start with the display and use case: 4947, 5205 or 5396 for a classic calendar; 5726 or 5261 for a sportier format; 5905 for a flyback chronograph; 5326 for travel; or 5235 for a regulator display.
Can I set every Patek Philippe Annual Calendar the same way?
No. Corrector locations, added functions and restricted setting windows can differ by reference and calibre. Use the official instructions for the exact watch and never force a corrector.
Evidence and methodology
Official sources and verification
Mechanism history, functions and calibre associations were checked against Patek Philippe's official calendar-watch and reference pages on August 22, 2026. The linked watch photographs and availability were reviewed on the same date. Specifications and availability can change.
Calendar system and collection
Combined and sport references
From mechanism to exact watch
Choose the display. Decode the calibre. Verify the record.
Tell the Superlative Watch Co. Buying Desk the reference, metal, dial, display, condition and ownership profile you want. We will confirm the exact-watch facts, availability and transaction path before you commit.
Written by the Superlative Watch Co. Buying Desk and published by Superlative Watch Co. Published ; last reviewed and modified . Superlative Watch Co. is an independent luxury-watch dealer and educational publisher; it is not affiliated with or authorized by Patek Philippe. Representative manufacturer imagery does not depict an exact inventory watch unless explicitly identified. Product availability and specifications can change.
