Nautilus 5726/1A-010 Unboxing: Patek's White Dial Annual Calendar
The Patek Philippe Nautilus 5726/1A-010 is one of the sleepers in the Nautilus family. When most people picture a Nautilus, they think dark dial, minimal complication, maybe just a date. The 5726/1A-010 isn't that watch. It's a high-contrast white dial with a full annual calendar — day, month, date by hand, and moon phase — wrapped in the same steel sports case the Nautilus is known for. It currently trades for considerably less than a 5711 or 5811, which makes it one of the more interesting steel Nautilus references on the market right now. Here's what stood out to us when we unboxed this one.
Table of Contents
The Watch
The 5726/1A-010 in its Patek Philippe presentation box at unboxing
Case Dimensions and Wrist Presence
The 5726/1A-010 has a 40.5mm stainless steel case with a lug-to-lug measurement just under 46mm. Patek lists thickness at 11.3mm, though we measured 12.1mm with calipers on this specimen. As always, our caliper readings are for reference, not gospel.
Case thickness measured at 12.1mm with calipers, against Patek's listed 11.3mm
Lug-to-lug measured at 45.5mm with calipers, just under Patek's 46mm specification
It weighs approximately 143 grams on the scale, roughly a third of a pound. You'll feel it on the wrist, but the integrated bracelet and slim case profile keep it balanced. This is a substantial steel Nautilus, not oversized but definitely not delicate.
On the scale at 143 grams (left) and 0.315 pounds (right), substantial but not heavy for a steel sports watch
The White Dial and Calendar Layout
The white dial is what completely changes the personality of this Nautilus. Most references in this family lean darker and simpler. The 5726/1A-010 is high contrast and visually active. The day and month apertures sit together at 12 o'clock, just below the Patek Philippe signature. The date is read by a central hand pointing to a 31-day track, and the moon phase is integrated into the date sub-dial at 6 o'clock.
The layout is structured but layered. Day and month apertures anchor the top half of the dial; the date hand and moon phase balance the bottom. The typography of the calendar apertures reads slightly different from the font used elsewhere, but the elements stack cleanly without feeling busy. Each piece has its own identity, and they hold together better than you'd expect from a dial doing this much work.
The white dial showing the day and month apertures at 12 o'clock and the moon-phase date sub-dial at 6 o'clock
Macro detail of the date track and moon-phase aperture at 6 o'clock with the central date hand
The applied hour markers and hands carry a useful amount of Super-LumiNova for low-light reading.
Super-LumiNova application across the applied hour markers and hands
Case Finishing and Bracelet
The case follows the Nautilus polished-and-satin convention, with brushed top surfaces broken up by polished case flanks. The integrated stainless steel bracelet has brushed links with polished accents that taper toward the folding clasp. There's no on-the-fly extension system on this reference. It's meant to be sized properly and worn as a complete cohesive design.
Brushed and polished bracelet link detail showing the case-to-bracelet transition
Folding clasp detail revealing the polished and satin finishing transitions
Caliber 324 S QA
Inside is the Patek Philippe self-winding caliber 324 S QA, the brand's annual calendar movement with moon phase. It carries a 21-karat gold rotor and a power reserve in the ~35-45 hour range. The annual calendar mechanism automatically adjusts for months with 30 and 31 days; you only need to correct it once per year, at the end of February.
The sapphire caseback normally shows the Geneva striping and applied finishing the caliber is known for, though on this particular watch the view is partially covered by a retailer warranty sticker.
Caliber 324 S QA visible through the sapphire caseback with retailer warranty sticker partially obscuring the rotor
How It Wears
The 40.5mm diameter combined with the integrated bracelet keeps the 5726/1A-010 sitting flat and balanced. The 143 grams gives it real wrist presence without crossing into heavy territory. The thickness is the trade-off for fitting the annual calendar mechanism inside the Nautilus footprint, and at 12.1mm it's still slim relative to most multi-complication sports watches.
The Nautilus 5726/1A-010 on the wrist showing case proportions and integrated bracelet flow
FAQ
What is an annual calendar?
An annual calendar tracks the day, date, and month and automatically adjusts for months with 30 or 31 days. It needs one correction per year, at the end of February, because it doesn't account for February's 28 or 29 days. A perpetual calendar handles February automatically; an annual calendar doesn't.
How does the 5726/1A-010 compare to the 5711 or 5811?
Same Nautilus design language, same 40-something-mm steel case, but the 5726 carries a full annual calendar with moon phase where the 5711/5811 are time-and-date. On the secondary market the 5726/1A-010 currently trades below both, which is unusual given it has substantially more complication.
What movement powers the 5726/1A-010?
The Patek Philippe self-winding caliber 324 S QA, with a 21-karat gold rotor, an annual calendar mechanism, moon phase, and a ~35-45 hour power reserve.
Does the 5726/1A-010 bracelet have a quick-extension clasp?
No. The 5726/1A-010 uses Patek's standard folding clasp without an on-the-fly micro-adjust system. It needs to be sized properly out of the gate.
Final Thoughts
The 5726/1A-010 is one of the more interesting steel Nautilus references currently on the market. It carries a full annual calendar with moon phase in the same case footprint that built the family's reputation, and the white dial gives it a different visual personality than most of its siblings. We think it's worth a serious look for anyone who wants a steel Nautilus with real mechanical depth and a dial that earns a second glance.
If you'd like to see the 5726/1A-010 in person or have questions about availability, reach out to us at watchesoff5th.com or through our social channels at @watchesoff5th.