Few manufacturers have approached the chronograph with the same degree of deliberate, long-term intent as Patek Philippe. What began in 2005 with calibre CHR 27-525 PS—at the time the world's thinnest split-seconds chronograph movement—was less a product launch than the opening move in a sustained program to build an entirely manufacture-developed chronograph family from the ground up. Calibre CH 29-535 PS arrived in 2009, bringing a column wheel, horizontal clutch architecture, and six patented innovations to a manually wound base that remains one of the most rigorously constructed in contemporary watchmaking.
The Grand Complication step came in 2011, when a perpetual calendar module was integrated to create calibre CH 29-535 PS Q—the engine that drives the 5270 and 5271 to this day. The split-seconds version, calibre CHR 29-535 PS Q, followed in 2012, and with it came reference 5204: a 40 mm manually wound split-seconds chronograph with perpetual calendar carrying 496 parts, and one of the most technically concentrated watches Patek has produced in the modern era.
Things to Know About the Watch
The new Patek Philippe Split-Seconds Chronograph Perpetual Calendar ref. 5204G-010, introduced at Watches and Wonders 2026, adds a new chapter to that lineage. 18K White gold, a navy blue sunburst dial, and contrasting red accents on the hands and the composite strap's stitching give this iteration a sporting register that the reference hasn't previously explored. For a watch built around two of horology's most demanding complications, it wears the combination with a confidence that feels entirely earned.
The 5204G-010 wears a fully polished 40mm white gold case at 14.3 mm thick—substantial, as any split-seconds perpetual calendar must be. The navy sunburst dial features a white tachymeter scale printed around the perimeter, the day and month in a double aperture at 12 o'clock, and moon phases with the date at 6 o'clock. Small round apertures show the day and night indicator and the leap year indicator at each side of the date indication.
The 30-minute counter sits at 3 o'clock; small seconds at 9 o'clock. It ships with both a navy composite strap with fabric pattern and red stitching, and an additional dark blue alligator strap—also with red stitching. Interchangeable solid and sapphire crystal case backs are included.
The Movement
Composed of 496 parts, the manual-wound calibre CHR 29-535 PS Q is considered one of the most demanding complications Patek Philippe produces. The split-seconds mechanism uses two column wheels and a horizontal clutch—a classical architecture executed to the highest standard. Power reserve runs 55 to 65 hours with the chronograph disengaged.
On the Wrist & Price
On the wrist, the Patek Philippe Split-Seconds Chronograph Perpetual Calendar ref. 5204G-010 makes a strong case for its own sporting ambitions. The navy composite strap, with its woven-fabric texture and red stitching, pulls the entire palette together. The white-gold case, navy sunburst dial, red chronograph hands, and split-seconds make all the parts read as cohesive rather than busy.
At 40 mm, it wears with presence without crossing into uncomfortable territory, and the dial, dense as it is with information, remains surprisingly legible in person. The red accents do real work here: they give the eye an anchor point amid the tachymeter scale, the perpetual calendar apertures, and the twin subdials, preventing the whole from collapsing into visual noise. This is a grand complication that does not insist on being solemn about it—and for a certain kind of collector, that is exactly the point.
Sticker Price USD 380,971. For more info on Patek Philippe click here.
