What's The Difference: Annual Calendar Vs Perpetual Calendar

Posted By: sarah

Published to Patek Philippe on Jul 02, 2021

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Most watches with a calendar function need to be regularly adjusted to ensure that the correct date is displayed. These watches reset after 24 hour cycles but because our calendar contains a varying number of days in each month, watchmakers had to develop a solution to combat having to constantly adjust watches. Two types of Complications were created to track our yearly calendar so that the date doesn’t have to be adjusted every month. These two types of Complications are known as Annual Calendars and Perpetual Calendar. But what is the actual difference between an annual calendar and a perpetual calendar? Read our guide looking at annual calendar vs perpetual calendar to find out more.


What Is An Annual Calendar Watch?


An annual calendar is a type of Complication that displays the date on a watch. An annual calendar watch displays the day, date and month requiring minimal adjustment. The annual calendar automatically adjusts the date displayed on the timepiece based on 30- and 31-day months to ensure that the correct date is always displayed. As our calendar contains leap years and months with fewer days than others, this Complication requires the date setting once per year, at the end of February. The movement does not account for the shorter month or leap years. For the other 11 months in the year, the movement will automatically adjust between 30 or 31 days. Although watch calendars have been in common use for some time, the annual calendar wasn’t introduced and patented until 1996 by Patek Philippe.


How Does An Annual Calendar Work?


Similar to the day-date complication, the day, date and month complication also known as the annual calendar commonly sit on wheels that rotate each day and are displayed through an aperture. Only requiring adjustments once a year, the annual calendar mechanism offers a more accessible, innovative and user-friendly complication. The annual calendar sits in the middle of the plain calendar, which needs adjusting five times a year for months of less than 31 days, and the perpetual calendar, which requires no adjustment whatsoever. 


What Is A Perpetual Calendar Watch?


The perpetual calendar is also a type of Complication that displays the date on a watch. Still displaying the day, date and month, the perpetual calendar requires less adjustment than the annual calendar. This complication not only knows the number of days in each month, but it also knows the year so that it will automatically adjust for the leap year. The next time a perpetual calendar will have to be adjusted is in the year 2100.


How Does A Perpetual Calendar Work?


A perpetual calendar is designed to display the day, date, and year correctly until the year 2100, taking into account any leap years, 28-days in February, and the difference between 30 and 31 day months. Not only can it do all of that but this impressive piece of machinery also typically indicates the year, moonphase, and highlights a leap year indicator. The movements powering a perpetual calendar are intricate and complex and hundreds of mechanical parts can be used.  The movement uses the wheels, gears, and levers to calculate the 1,461 days (four years) and calculate the correct date.


Annual Calendar Vs Perpetual Calendar


The main difference between an annual and perpetual calendar is having to set the watch for February and leap year. An annual calendar accounts for the 30-day months and 31-day months, with a manual adjustment at the end of February. Whereas the perpetual calendar works “perpetually” and will only need an adjustment in 2100 when the leap year is skipped.



Best Patek Philippe Annual Calendar Watches

Patek Philippe 5396R



The Patek Philippe 5396R was released to celebrate the 20th anniversary of the original first patented annual calendar launched by Patek in 1996. Featuring a rose gold case, the Patek Philippe 5396R-011 has a design that never goes out of style. With a silvery opaline dial, gold applied hour markers and sapphire-crystal case back, the Patek Philippe 5396R-011 has a flawless sleek design.


Patek Philippe 5235/50R-001



The Patek Philippe 5235/50R-001 revisits the unique style of its Annual Calendar Regulator by presenting it in a rose gold case. With a two-tone graphite and ebony black dial, with vertical satin finish and white transfer print and sapphire-crystal case back, the Patek Philippe 5235/50R-001 is as sophisticated as it is practical.


Patek Philippe 4947G-001



The Patek Philippe 4947G-001 ladies watch has a patented annual calendar that only needs to be corrected once a year. Featuring a white gold case, the Patek Philippe 4947G-001 has a bold feminine design. With a metallic blue dial, gold applied numerals and sapphire crystal case back, the Patek Philippe 4947G-001 has a cool and elegant design.


Best Patek Philippe Perpetual Calendar Watches


Patek Philippe 5270/1R-001



The Patek Philippe 5270/1R-001 Grand Complications has a manually wound mechanical movement and a CH 29-535 PS Q Caliber. This Grand Complications has an ebony black sunburst dial, displaying the day and the month in a double aperture at 12 o’clock and an analogue date at 6 o’clock. In addition to oozing a luxury feel, the Patek Philippe 5270/1R-001 also has sandblasted hands, which combines sleek style with modern legibility. The Patek Philippe 5270/1R-001 has a rose gold “Gouette” bracelet that perfectly blends with the case for a seamless finish.


Patek Philippe 5496P-015



The Patek Philippe 5496P-015 Grand Complications has a self winding mechanical movement and a 324 S QR Caliber. This Grand Complications has a platinum case and sapphire crystal case back protected by a hinged dust cover. This particular model also takes advantage of Patek Philippe’s mechanical memory function which allows the calendar to show day, date, month and leap year days. The Patek Philippe 5496P-015 has an Opaline-white dial, hand guilloched centre and rose gold polished hour markers and hands that is a watch collector's dream. 


Patek Philippe 5320G-001



The Patek Philippe 5320G-001 Grand Complications has self winding mechanical movement and perpetual calendar and day, date, month, leap year and 24-hour indicators. The Patek Philippe 5320G-001 has an 18k white gold case with an Interchangeable full back and sapphire-crystal case back and sweep seconds hand. This Grand Complications case has three-tier lugs as well as a lacquered cream dial including luminous numerals and hands. The Patek Philippe 5320G-001 has a newly developed calibre 324 with double apertures for the day/month and an analogue date and is highly desired by watch collectors and enthusiasts alike.


If you own a Patek Philippe timepiece with an annual or perpetual calendar and are looking to sell or get a quote, then we are here to help. With our Get A Quote from it's never been easier to have your watch valued. Sell your Patek Philippe watch to us and receive the best possible price.

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