Audemars Piguet Royal Oak Selfwinding Ref. 15500ST

Fifty years of getting bigger

The Royal Oak began in 1972 as a 39mm steel watch, so large for its day that it earned the nickname 'Jumbo.' Then the line shrank: according to one collector's history of the model, the 36mm watches of the 14000 series dominated the range from 1983 to 2005.

The trend reversed when oversized watches took over the industry, a shift Audemars Piguet's own archive credits partly to its Royal Oak Offshore of 1993. In the brand's account, the 36mm Model 14790 gave way to the 39mm Model 15300 in 2003, and the 15300 was surpassed in 2012 by the 41mm Model 15400. The collector's history dates the 15300 to 2005 instead, so the exact year is disputed.

The 15400 kept the 15300's movement, Calibre 3120, which measures 26.6mm across. In a 41mm case that pushed the date window well in from the edge of the dial, and Audemars Piguet added a short hour marker beside the window to fill the gap. Some collectors also complained that the movement looked too small behind the sapphire caseback.

A new engine in a familiar case

Audemars Piguet's answer arrived in January 2019 at the SIHH fair in Geneva. Most of the attention that week went to Code 11.59, a new collection with a new family of in-house movements. One of them, the automatic Calibre 4302, also went into a new Royal Oak: the 15500. The brand describes the 4302 as 'the simple hour, minute, centre second and date movement launched in 2019.'

Calibre 4302 measures 32mm across, so for the first time the 41mm Royal Oak had a movement sized for its case. It runs at 4 Hz (28,800 vibrations per hour), has 70 hours of power reserve instead of the 3120's 60, and is built from 257 parts with 32 jewels in a height of 4.9mm. Through the caseback you see Geneva stripes on the bridges, polished bevels and an openworked 22-karat gold rotor.

The larger movement changed the outside of the watch only slightly. The case stayed 41mm wide but grew to 10.4mm thick from 9.8mm, according to a launch review; Audemars Piguet's own specification lists 10.5mm. Water resistance stayed at 50 meters with a screw-locked crown, and the octagonal bezel kept its eight white gold screws.

How to tell a 15500 from its neighbors

Look at the date first. With a larger movement underneath, the date window moved back out toward the edge of the dial, and the short applied marker that sat beside the 15400's window disappeared.

Next, look at the edge of the dial. Among the steel three-hand 41mm Royal Oaks, the 15500 is the only one with a plain, untextured minute track. Its 'Grande Tapisserie' pattern stops short of the edge and leaves a smooth ring printed with 60 thin white markers. The tapestry itself was reworked, with thinner grooves and slightly larger squares. The hands and hour markers are broader and hold more luminous material, the hour markers are shorter, and the seconds hand gained an open counterweight. There is no 'Automatic' line at six o'clock.

Steel versions came on a bracelet with four dial codes: 01 blue (a boutique exclusive at launch), 02 grey, 03 black and 04 silver. At launch Audemars Piguet also offered pink gold versions on a gold bracelet or on leather.

On the successor 15510, the tapestry runs all the way to the bezel again, the hour markers are longer and the 'AP' logo is gone from the dial. A plain minute ring plus a date at the edge means you are looking at a 15500.

The waiting list and the market

Demand outran supply. One collector wrote that he began emailing boutiques in February 2019, a month after the launch, because 'too many people were after the 15500.' He gave the brand's total output across all models as about 40,000 watches in 2020. Four years later a boutique finally called, and the watch it offered was the 15500's successor.

Sources disagree on when the 15500 left the catalog. One reference guide says it was discontinued in 2021. The collector's history says the 15510 replaced it in 2022, first as a 50th-anniversary edition with a special rotor and then, from 2023, as the regular model. Yet in October 2026 the brand's US website still listed the blue-dial 15500ST.OO.1220ST.01 at $31,900, the same price as the 15510ST.

On the secondary market, dial color matters a great deal. An April 2024 guide valued the blue dial at about $55,000 and the silver dial, the least sought-after, at about $37,000, with grey and black near $40,000. Recorded sales have landed lower than those figures. A silver-dial 15500ST sold online at auction in New York in June 2024 for $32,760. Another sold online in Geneva in November 2024 for CHF 30,240, and one in Hong Kong in May 2023 brought HKD 352,800.

The bridge to the modern Royal Oak

In the history of the line, the 15500 is where the core 41mm Royal Oak first got a movement built to its size. Its predecessor had used a movement from a smaller case. Its successor, the 15510, kept the same Calibre 4302 and refined the dial.

It also sits at the center of an argument over which Royal Oak is the 'real' one. A 2024 guide put it this way: purists say the 39mm models are the true heirs of the 1972 'Jumbo,' while newer collectors see 41mm references like the 15500 as the full-size Royal Oak.

As an object it is easy to date. An edge-mounted date, a plain printed minute ring and broad luminous markers belong to this reference alone. It came between the 15400 and the 15510.

The numbers

Reference

15500ST.OO.1220ST.01 (blue), .02 (grey), .03 (black), .04 (silver)

Caliber

Audemars Piguet 4302, self-winding, 32mm, 4.9mm thick, 28,800 vph (4 Hz), 32 jewels, 257 parts, 70-hour power reserve, 22-karat gold rotor

Case

41mm stainless steel, 10.4mm (2019 review) or 10.5mm (brand), sapphire crystal and caseback, screw-locked crown, 50m

Dial

'Grande Tapisserie' with plain printed minute track, white gold applied markers, luminescent Royal Oak hands

Bracelet

Integrated steel bracelet with AP folding clasp

Production

From January 2019; end date disputed (2021 per one guide, 2022 per another); still listed by the brand in October 2026

Launch prices

CHF 19,300 steel; CHF 50,700 pink gold on bracelet; CHF 32,100 pink gold on leather

Timeline

1. 1972

   Audemars Piguet launches the Royal Oak, a 39mm steel watch later nicknamed the 'Jumbo.'

2. 1983

   The 36mm 14000-series models begin a long run at the core of the line, lasting to 2005 per one collector's history.

3. 2003

   Per the brand's archive, the 36mm Model 14790 gives way to the 39mm Model 15300 (another account dates the 15300 to 2005).

4. 2012

   The 41mm Royal Oak Selfwinding ref. 15400 arrives, still using Calibre 3120.

5. Jan 2019

   The 15500 is unveiled at the SIHH fair in Geneva with the in-house Calibre 4302, priced from CHF 19,300 in steel.

6. Feb 2019

   One collector starts writing to boutiques for a 15500; his wait lasts four years.

7. 2021

   One reference guide dates the 15500's discontinuation to this year.

8. 2022

   The 15510ST '50th Anniversary' appears with the same Calibre 4302 and a commemorative rotor.

9. 2023

   The 15510ST continues as the regular model, with new dial codes 06 to 10.

10. May 26, 2023

    A 15500ST sells online in Hong Kong for HKD 352,800.

11. Jun 14, 2024

    A silver-dial 15500ST sells online at auction in New York for $32,760.

12. Nov 20, 2024

    A steel 15500ST sells online in Geneva for CHF 30,240.

13. Oct 2026

    The brand's US website lists the blue-dial 15500ST.OO.1220ST.01 at $31,900.

The world in 2019

• Jan 2019

  At the same Geneva fair, Audemars Piguet launches the Code 11.59 collection, which uses the same new Calibre 4302.

• Jan 28, 2019

  The US Justice Department charges the Chinese tech firm Huawei with fraud, raising US-China tensions.

• Apr 10, 2019

  Scientists from the Event Horizon Telescope project announce the first image of a black hole.

• Apr 15, 2019

  Fire engulfs Notre-Dame Cathedral in Paris, collapsing its roof and main spire.

• Jun 15, 2019

  Hong Kong suspends its controversial extradition bill, but protests continue.

• Jul 24, 2019

  Boris Johnson becomes Prime Minister of the United Kingdom.

• Dec 1, 2019

  The first known human case of COVID-19 occurs in Wuhan, China.

Price record

A realized auction price is what a buyer actually paid on the date shown, including the buyer's premium where the sale reported it. It is the strongest kind of reference price, and it is a record of one sale of one object on one day, not a promise of what the next example will bring.

By reference price, Audemars Piguet Royal Oak Selfwinding Ref. 15500ST is number 53 of 100 in the watches entries of the FLOAT 100. 54 of those 100 rest on a realized sale; the rest carry an asking price or a guide value, and each page says which. Rank within the FLOAT 100 itself (45 here) is editorial: how much an object defines its field, not price alone.

Did you know

• The 15500's movement launched the same week in a different watch: Calibre 4302 also powers the Code 11.59 Selfwinding.
• Among the steel three-hand 41mm Royal Oaks, the 15500 is the only one with a plain, untextured minute ring around the dial.
• At launch the blue-dial steel 15500 was sold only in the brand's own boutiques; the grey and black versions also went to retailers.
• The 15400 it replaced had an extra short hour marker beside the date, there only because its smaller movement pushed the date window toward the center.
• Its successor kept the same movement but dropped the 'AP' logo from the dial, which makes the two easy to tell apart.
• One collector waited four years for a boutique to call, and when it finally did, the watch on offer was the 15500's successor.