Watch Complications Explained for Buyers: Date, GMT, Chronograph, Calendar and Beyond

A watch complication is any function a mechanical movement performs beyond showing hours, minutes and seconds. The date is the simplest and the most common; a second time zone, a chronograph, an annual or perpetual calendar, a moon phase, a tourbillon and a minute repeater sit above it in roughly that order of mechanical difficulty, cost and servicing complexity. For a buyer the questions are practical: what does each complication do, will you use it, what does it add to the price new and used, and what does it cost to keep running. This guide answers those for the complications found across Rolex, Patek Philippe, Audemars Piguet and Richard Mille, with the references that carry each one. The Patek Philippe Complications collection covers the middle of the range, where most buyers of a first complicated watch end up.

Last reviewed on September 25, 2026 by Filip Biczak. Prices are dated observations, not quotes.

Watch complications at a glance

Patek Philippe's own catalogue divides these into "Complications" and "Grand Complications"; the Complications page covers annual calendars, travel time and chronographs, and the Grand Complications page covers perpetual calendars, tourbillons, repeaters and combinations of them.

What is a watch complication?

The term comes from the watchmaking trade, where anything added to the basic going train that shows the time complicates the movement. A date disc driven once a day counts; so does a repeater with hundreds of parts. The word carries no judgement about usefulness. A date is the complication most owners use daily, a chronograph is used by most owners occasionally, and a tourbillon is used by nobody, since it works whether or not you look at it. What every complication shares is that it adds parts, and parts add cost to make, cost to service and points at which something can go wrong or be set incorrectly by an owner. That is the trade a buyer makes.

Date, day-date and the calendar complications

A simple date needs correcting after every month shorter than 31 days, which is five times a year. Rolex's quickset date, on every current Datejust and Submariner Date, makes that a few turns of the crown in the first position. An annual calendar, which Patek Philippe patented and introduced in 1996 on the reference 5035, adds a mechanism that knows which months have 30 days, so it needs one correction a year, on 1 March, because it cannot tell how long February was. Rolex's Sky-Dweller of 2012 combines an annual calendar with a second time zone and sets both through its Ring Command bezel. A perpetual calendar adds a four-year cam that accounts for February and leap years, so the display is correct until 2100, when the Gregorian calendar skips a leap year. Patek Philippe's Nautilus 5740 of 2018 put a perpetual calendar into the Nautilus case for the first time, using the ultra-thin calibre 240 Q, and Audemars Piguet's Royal Oak Perpetual Calendar does the same in the Royal Oak. The Rolex watch pages describe the Sky-Dweller's calendar and the Audemars Piguet collection pages the Royal Oak Perpetual Calendar's.

GMT, dual time and world time

A GMT watch shows a second time zone with a fourth hand that makes one turn a day, read against a 24-hour scale on the bezel or the dial. Rolex's GMT-Master of the 1950s was built for airline crews, and the current GMT-Master II lets the wearer jump the 12-hour hand in one-hour steps while the 24-hour hand stays on home time, so it shows two zones with the rotating bezel offering a third. The Explorer II uses the same movement logic with a fixed bezel. Patek Philippe's Travel Time mechanism, on the Aquanaut 5164 and the Nautilus 5990, shows two hour hands and two day-night apertures and moves the local hand with pushers. A world timer, which Patek Philippe has made since the 1930s and currently offers as the 5230, shows all 24 zones at once on a rotating city ring. For a buyer who travels, the GMT is the most useful complication after the date; our GMT-Master II Batman guide explains how the Rolex version is set and read.

Chronographs: what to know before buying one

A chronograph is a stopwatch built into the watch, started, stopped and reset with pushers, with elapsed time read on subdials. The Rolex Daytona, in its current 126500LN form with the calibre 4131, is the most requested chronograph in the world; Patek Philippe's 5172 and 5905, Audemars Piguet's Royal Oak Chronograph and Richard Mille's RM 011 cover the rest of the market. Three things matter to a buyer. First, the mechanism: a column-wheel chronograph with a vertical clutch, as in the Daytona and the Patek Philippe CH 29-535, starts without the seconds hand jumping and can be left running without wearing the movement; cheaper cam-actuated designs can jump on start. Second, the variants: a flyback resets and restarts with one press, and a rattrapante or split-seconds has two seconds hands for timing two events, which roughly doubles the complexity and the service bill. Third, the discipline: never operate the pushers under water on a Daytona, and never reset a chronograph while it is running unless it is a flyback. Our Daytona 126500LN guide covers the current Rolex chronograph in detail, and the chronographs collection shows the references Bizak can source.

Moon phase, tourbillon and minute repeater

A moon phase is a disc with two moons that turns once every 59 days behind an aperture, showing the moon's current shape. The standard 59-tooth wheel drifts by about a day every two and a half years; Patek Philippe and Audemars Piguet's high-precision versions run for over a century between corrections. It is decorative rather than useful, and it is the complication most often paired with a calendar. A tourbillon is a rotating cage that carries the balance and escapement through every vertical position, invented to average out the effect of gravity on a pocket watch that spent its life upright; in a wristwatch that moves all day it has no measurable benefit, and it is bought for the mechanism itself, visible through the dial. Richard Mille built its reputation on tourbillons light enough to wear playing tennis, and the Richard Mille collection pages list the current ones. A minute repeater chimes the hours, quarters and minutes on two gongs when a slide is pulled, and it is the most demanding complication to make and to regulate, which is why Patek Philippe and Audemars Piguet still make each one largely by hand and why a repeater sits at the top of both catalogues.

Which complications are worth buying?

The general rule is that a complication earns its place if you will use it or look at it, and that every complication you will not use is a service cost with no benefit.

What complications mean for price and servicing

At retail, each step up the table roughly multiplies the price: a Nautilus 5811 time-and-date and a Nautilus 5740 perpetual calendar share a case family and differ by several times in list price. On the secondary market the picture is different. Time-and-date steel sports models from Rolex, Patek Philippe and Audemars Piguet carry the largest premiums over retail because demand is widest; complicated watches in precious metal more often trade below their original retail, so a used perpetual calendar can be the better value per hour of watchmaking. On 25 September 2026 Bizak's sourced catalogue listed a Nautilus 5740/1G perpetual calendar at US$298,695 new and a pre-owned example at US$249,290, a Sky-Dweller 336934 in steel and white gold at US$27,225 and a Daytona 126500LN at US$33,990, all sourced to order. Those figures describe what we saw and will move. Servicing scales the same way: a simple automatic is serviced at the brand for a fixed fee every several years, a chronograph or annual calendar costs more, and a perpetual calendar or repeater is serviced only by the manufacturer's own specialists, which means longer turnaround and a higher invoice. The Rolex watch care and service page sets out the brand's service intervals, and Patek Philippe undertakes to service every watch it has made. Our Patek Philippe price guide shows dated asks across simple and complicated references.

Buying a complicated watch: what to check

• Every function works. Advance the date through a month end, set the second time zone, run and reset the chronograph, and watch the moon disc move; a complication that has not been exercised for years can stick.
• Correct setting sequence. Perpetual and annual calendars must not be set during the hours around midnight when the mechanism is engaged; ask the seller to demonstrate the safe window and check the manual for the reference.
• Correctors and pushers. Recessed correctors on a calendar watch should move cleanly with the supplied stylus; chronograph pushers should have a firm, even action and reset the hands to exactly zero.
• Service history. A complicated watch with no service record is a watch whose next service is unbudgeted; ask for the last invoice and who did the work.
• Papers and extract. Patek Philippe and Audemars Piguet complicated references should come with the certificate or an extract from the archives that matches the movement and case numbers.
• Warranty transfer. Check what remains of the manufacturer's warranty and whether it covers the complication as well as the base movement.
• Price against the band. A full-set complicated watch offered well under the market is the single most reliable warning sign.

Our authentication process includes function testing every complication before dispatch.

Quick answers

What is a complication in a watch?

Any function beyond hours, minutes and seconds. A date is a complication; so are a second time zone, a chronograph, a calendar, a moon phase, a tourbillon and a repeater.

What is the difference between an annual calendar and a perpetual calendar?

An annual calendar knows which months have 30 or 31 days and needs correcting once a year, on 1 March. A perpetual calendar also accounts for February and leap years and runs correctly until 2100.

Is a tourbillon worth it?

Not for accuracy in a wristwatch. It is bought as a visible piece of mechanism, and it should be bought from a maker with its own service department.

Which complication is the most useful?

The date for daily wear, and a GMT with an independent hour hand for anyone who travels. A chronograph is useful occasionally; the rest are for interest.

Do complicated watches hold their value?

Less reliably than simple steel sports models, which carry the largest premiums. Complicated watches in precious metal often trade below original retail, which makes them better value per hour of watchmaking when bought used.

Request a complicated watch sourcing quote

Tell us the reference, metal, dial, preferred year range, condition and whether papers are required, plus your budget and timing, through our sourcing enquiry form. We confirm the specific watch, photographs, papers and final price before you commit. Catalogue entries: Patek Philippe Nautilus 5740/1G perpetual calendar, Rolex Sky-Dweller 336934, Rolex Daytona 126500LN; browse the Patek Philippe Grand Complications collection, the perpetual calendar collection, the GMT watches collection, or sell or trade your watch.

Related reading: Patek Philippe Nautilus 5740 guide · Rolex Daytona 126500LN guide · GMT-Master II Batman guide · Nautilus 5990 Travel Time guide.