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Moon phases are one of the most prevalent complications in watches. Humanity has always been fascinated with the heavens above, so it’s no surprise that watchmakers found a way to capture the moon’s beauty in a watch and track the lunar cycle. Moon-phase watches range from métiers d’art masterpieces to complicated calendars and elegant dress watches. There are even some luxury sports watches with moon-phase indicators. 

Many watchmakers use the moon-phase disk to showcase their métiers d’art. Mother-of-pearl and aventurine are frequent materials because glittering blue aventurine evokes a starry night sky. The texture and shimmer of mother-of-pearl represent the craters on the glowing moon. Other techniques include using hammered metal for the moon, painting the moon, or using enamel. Clouds and stars frequently decorate the disk, too. 

Here, we explain everything you need to know about how moon-phase indicators work and showcase the finest luxury moon-phase watches. 

In This Article

• How Does a Moon Phase Work?
• What Are the Different Types of Moon-Phase Watches?
• The Best Luxury Moon-Phase Watches

How Does a Moon Phase Work? 

As its name suggests, a moon-phase complication shows the phase of the moon, which is the moon’s illuminated area. Typically, there’s a disk underneath the dial decorated with two moons placed opposite of each other. The dial has a window that the disk peeks through. The disk rotates accordingly as the moon moves through its 29.5-day cycle as seen from Earth. At first, just a small sliver will show through the aperture on the dial, indicating a waxing crescent moon. The moon will grow larger until it’s completely revealed at the full moon. The disk continues to rotate, and the dial begins to hide the other side of the moon as it becomes a waning crescent moon. Then, the first moon on the disk disappears underneath the dial to indicate the new moon. Finally, the second moon emerges on the other side as a waxing crescent moon, and the cycle continues. Of course, some watchmakers take a different approach, but the concept remains the same. 

What Are the Different Types of Moon-Phase Watches?

There are different levels of precision when it comes to a moon-phase timepiece. Some track the moon phase and need to be updated every few years to account for slight discrepancies in the lunar calendar. Others don’t need to be corrected for hundreds or thousands of years. 

Of course, these watches will only remain accurate if you wind them regularly and they run uninterrupted. If the watch loses power and stops keeping time, you’ll need to set your watch and reset the moon phase. This is one reason why a long power reserve is a good idea on a moon-phase watch. These watches can be fiddly to set using tools, so if you aren’t likely to keep your watch wound, look for one that’s easy to correct using the crown or a pusher. 

Simple Moon Phase

A simple moon phase will be driven by a gear that has 59 teeth (the 29.5-day lunar cycle times two), advancing by one tooth each day. However, the moon’s cycle isn’t exactly 29.5 days; it’s 29 days, 12 hours, 44 minutes, and 2.88 seconds, or 29.53 days. Over time, this discrepancy builds up, and the moon phase will need to be adjusted every three years. 

Astronomical Moon Phase

To counter this discrepancy, astronomical moon phases use a 135-tooth gear. Astronomical moon phases are typically precise for 122 years until there’s a slight deviation from the moon’s actual position. After 122 years, a watch’s moon phase will need a one-day correction to remain accurate for another 122 years. Some are accurate to 125 years. Some watchmakers have raised the bar with an even more precise moon phase that deviates by one day every 577.5 or 1,028 years. In 2024, IWC Schaffhausen shattered all records with its new Portugieser Eternal Calendar, which has a moon phase that will be accurate for 45 million years. You can read more about how this marvel works below. 

Double Moon Phase

Another, more complicated, version is the double moon phase, which shows the moon phase in both the northern and southern hemispheres. Double moon phases can be simple or astronomical moon phases, depending on the movement. 

The Best Luxury Moon-Phase Watches

IWC Schaffhausen Portugieser Eternal Calendar

Watch brands love competing to set records, and in the case of the thinnest watches in the world, they fight to shave off fractions of millimeters. The race for the longest and most accurate moon phase likely ended in 2024 when IWC Schaffhausen introduced the Portugieser Eternal Calendar. This exceptional timepiece has a perpetual calendar that will be accurate until the year 3999 and a moon phase that should be accurate for 45 million years, after which it will deviate by a single day. (Really!) IWC’s previous moon-phase watches would be accurate for 122 years or 577.5 years, but the Portugieser Eternal Calendar uses a new reduction gear train to achieve unheard-of accuracy. In addition, this platinum watch has a double moon phase and displays the moon from both the Northern and Southern hemispheres. 

Arnold & Son Luna Magna

Arnold & Son takes a new approach to moon-phase watches with the Luna Magna watch. Instead of showing the moon phase on an engraved disc, it crafted a three-dimensional moon from marble and aventurine. At 12mm, it’s the largest moon to appear on a watch — hence the name Magna, which means “big” in Latin. To further emphasize the starry night sky, Arnold & Son used its signature small dial off-centered at 12 o’clock, leaving the rest open for aventurine. The moon phase isn’t just beautiful; it is very precise and will remain accurate for 122 years. The back of the watch has a secondary display showing the moon’s age. 

If you don’t keep the watch wound, it’s easy to reset the moon phase by using the crown. The watch features the A&S1021 caliber, which has a 90-hour power reserve. To accommodate the spherical moon, the front sapphire glass is gently domed. The watch measures nearly 16mm in thickness. 

Girard-Perregaux Cat’s Eye Celestial

The Cat’s Eye watch is one of the most iconic women’s watches, instantly recognizable for its unique East-West design — one of the more rare case shapes. It also has one of the larger moon-phase disks in the industry. Instead of a petite subdial, most of the top half of the dial is taken up by the moon phase, which measures 8.9mm in diameter. The dial and background of the disk are made from shimmering aventurine. The moon-phase disk features stars and planets alongside a magnificent mother-of-pearl moon. Glittering diamond hour markers and accents on the blue dial evoke more stars. The 18K rose gold case adds warmth to the cool-toned design, and more diamonds encircle the bezel. It features an automatic movement with a 46-hour power reserve. 

H. Moser & Cie. Endeavour Perpetual Moon

The creatives at H. Moser & Cie. love to upend traditional ideas of watchmaking in their timepieces and continually strive to raise the bar. It’s not enough for the company to debut its first moon-phase watch — it needed to be exceptional. The Endeavour Perpetual Moon features one of the most precise moon-phase movements in the market. If you keep it wound, it will accurately show the lunar cycle for 1,027 years. Thankfully, it has a seven-day power reserve, so you — and your descendants — have a shot at keeping it wound for a millennium.

The watch showcases H. Moser’s Concept design. The dial is missing many of the signature elements on other watches, including the brand name and hour markers. This lets the beauty of the blue dial crafted from aventurine shine through. A bit counterintuitively, by not having its name emblazoned on the dial, those in the know will instantly recognize it as an H. Moser timepiece. Without any distractions, the pure aventurine dial really evokes an endless night sky. The ultraprecise moon phase is at 6 o’clock. The sleek moon completes the minimalist dial.

Patek Philippe Ref. 5270P

Many perpetual calendar watches include moon phases, but no one does it quite like Patek Philippe. This Grand Complication watch includes a perpetual calendar, a chronograph, and a moon phase. Reference 5270P comes in an elegant platinum case with a unique concave bezel. Both perpetual calendars and chronographs show a wealth of information, typically using many subdials. Including all of this information while ensuring the dial remains legible can be challenging. 

Patek Philippe chose to display the chronograph time in two subdials, at 3 and 9 o’clock, and combined the date and moon phase in a subdial at 6 o’clock. Two small apertures flank this subdial. The left is a day/night indicator, and the right shows the year in the leap-year cycle. Two apertures in the center of the dial show the day of the week and the month. The watch has a rich green dial with applied hour markers, a railway-style minutes track, and a seconds track.

Hermès Arceau L’Heure de la Lune

You can be sure of two things when Hermès releases a new complicated watch. The French maison approaches complications in a unique way, frequently wowing us with never-before-seen movements, and every watch has a stunning design with a touch of whimsy. The Hermès Arceau L’Heure de la Lune reverses the traditional approach to moon-phase watches that have a rotating lunar disk. Instead, it has two stationary moons representing the moon phase in the northern and southern hemispheres, and two floating dials circle around the moons. One dial shows the time and the other the date. 

The extraterrestrial design is in full effect in these watches. The moons are crafted from mother-of-pearl. The northern moon represents the lunar surface, while the southern moon has a pegasus hidden inside of it. Hermès offers traditional dials in materials like aventurine and lapis lazuli, as well as three dials that are literally out of this world. These dials are real meteorites, so you can take a piece of outer space with you wherever you go. 

A. Lange & Söhne Richard Lange Perpetual Calendar “Terraluna”

The first thing you might notice about this moon-phase watch from A. Lange & Söhne is that it seems to be missing the moon phase. However, the Richard Lange Perpetual Calendar “Terraluna” displays far more information than a traditional artistic moon phase. It also displays a perpetual calendar on the front in a unique way and the moon phase on the back. 

The dial has three circles that display the time: one each for the hours, minutes, and seconds. At 12 o’clock, there’s a date aperture. The leap year is shown in a small window at 2 o’clock, the month at 4 o’clock, and the date in a slim cutout at 6 o’clock. The back of the watch displays an orbital moon phase that is so precise that it won’t need to be corrected for 1,058 years. The moon phase shows not only the progression of the lunar cycle but also the position of the moon in relation to the earth.

Chopard Imperiale Moonphase

Chopard uses the shimmering beauty of the aventurine dial to re-create the night sky in the Imperiale Moonphase watch. The dial features five constellations, including the Big Dipper, diamonds representing stars, and a small astronomical moon-phase display. It has large Roman numeral hour markers at 12, 3, and 9 o’clock, and at 6 o’clock, there’s a unique small seconds display. Three carats of diamonds cover the 18K white gold bezel and lugs. This watch features an in-house movement that is a certified chronometer and has a 65-hour power reserve.

Cartier Drive de Cartier Moon Phase

This classic dress watch from Cartier is perfect for those who are looking for an affordable luxury watch with a discreet moon phase. The Drive de Cartier Moon Phase has a stainless steel case with elegant Roman numeral hour markers that contrast nicely with the silvered dial. Inside, there’s a minute track. The astronomic moon phase peeks out just above 6 o’clock. The moon-phase disk is blue with a golden moon and stars. The Drive de Cartier Moon Phase has an automatic movement. It’s also available in pink gold. 

Jaeger-LeCoultre Rendez-Vous Moon Serenity

The stunning Rendez-Vous Moon Serenity from Jaeger-LeCoultre reserves most of its dial for a large mother-of-pearl moon phase and a rendition of the starry night sky. While the Rendez-Vous has a round case, it uses the space inventively. It displays hour numerals only on the top half of the dial in a golden cage shaped like a crescent moon. Beneath this is an oval filled with a satin-brushed star chart. The 18K rose gold bezel is set with 62 diamonds, and a golden star appears to shoot from it. This star indicates an appointment time, or a rendezvous. You set the star’s time by using the second crown. The watch has an open caseback, so you can admire the in-house movement, which has 38 hours of power reserve. 

Omega Speedmaster Moonphase

Not all moon-phase watches highlight métiers d’art; some focus on everyday wear. The Omega Speedmaster Moonphase is a perfect example of this. Also, the Speedmaster is the only watch that has actually been on the moon. It first launched in 1957, and NASA equipped every astronaut on each of the six lunar missions with a Speedmaster. At 6 o’clock, an astronomical moonphase features a high-resolution image of the moon. This 44.25mm steel sports watch also has a chronograph function and is a certified chronometer, so it precisely tracks the time. 

The central hand is the chronograph hand, the chronograph counter is at 3 o’clock, and the date and running seconds appear at 9 o’clock. The Speedmaster Moonphase comes in many colors, but we love this elegant black version. It has a black sun-brushed dial, contrasting rhodium-plated indexes and hands, and a black ceramic bezel. An in-house automatic movement powers the watch. It’s water-resistant to 100m and has a 60-hour power reserve. 

Rolex Cellini

You might be surprised to learn that at one point, Rolex had a beautiful dress watch with a moon phase: Cellini. Unfortunately, Rolex discontinued the Cellini collection in 2023. Fortunately, the brand replaced it with the time-only 1908 collection, but you can still find the Cellini at pre-owned watch retailers. It’s the only Rolex watch with a moon phase. The Cellini has classic stylings, including a polished 18K Everose case (the Rolex equivalent of rose gold) with a fluted bezel. The circumference of the white lacquered dial features a wealth of information. There’s a date track, a minute track, and applied hour markers. A long blue hand topped with a crescent moon points to the date.

At 6 o’clock, it has a large, shimmering astronomical moon phase crafted from blue enamel. Rolex takes a different approach to display the moon phase. Instead of having the disk with the moon rotate underneath the dial, it shows the new moon with a silver circle and the full moon, which is actually crafted from meteorite, at the same time. A gold arrow at the top of the moon phase shows the position in the lunar cycle.