Patek Philippe Creates New Caliber and Calendar Display in Calatrava Ref. 5328G

Patek Philippe has had a busy Watches & Wonders 2025, and while there are a number of standout references, including a new 40mm Cubitus, there is a Calatrava reference that brings a new movement to the collection, and with it, a new day and date calendar display. The Calatrava 8-Day, Ref. 5328G-001 Power Reserve, Instantaneous Day & Date showcases the manually wound 31-505 8J PS IRM CI J caliber (doesn’t exactly roll off the tongue) which boasts a full eight days of power reserve, and one of the most innovative calendar displays to come out of the brand. It’s placed within a 41mm white gold case that measures a mere 10.5mm in thickness, with a textured blue dial gracefully pulling everything together. 

A new movement from Patek always provides plenty of interesting mechanical insights to the brand, and this watch is no exception. This 8-day movement — which has its technical roots in the caliber developed for 2013’s Ref. 5200-G Gondolo 8-Days model — uses two coupled barrels that technically provide nine days of reserve, as indicated by the red final section of the power reserve display at the top of the dial. This is simply a reminder that the watch needs winding. While there are no accuracy measurements listed by Patek, it is presumably good enough to keep the watch within spec throughout the duration of the power reserve window. After all, what good is a long power reserve if you need to reset the time every few days to offset the drift. 

The other half of the dial features a unique calendar display nested into a single subsidiary dial space. This is a day-and-date display that’s surprisingly practical to read, placing the date at the outside perimeter of a track within which the running seconds hand is placed. At the center is an aperture with the day of the week. It’s a surprisingly simple approach to the most practical of complications. While the dial uses applied Arabic numeral hour markers, the two on either side of the calendar display are represented by applied circular markers. 

All of this is set within a deep blue textured dial that fades to a dark tone at the dial’s perimeter. It’s done in a subtle manner that balances out the grain texture that we’ve seen the brand use in years prior. The white-gold case measures 41mm in diameter, and features a guillochéd hobnail pattern along the case wall. This texture will also be familiar to fans of the brand, and brings a welcome level of detail when viewed at an angle. Around back, the movement is visible through an exhibition back, where you can enjoy the Pulsomax escapement with Silinvar escape wheel, which was initially developed as part of the Patek Philippe Advanced Research program.

The Patek Philippe Calatrava 8-Day ref. 5328G-001 joins the regular production collection, and will be priced at CHF 60,000.