How to Read a Rolex Datejust Reference Number

A Rolex Datejust reference number is a six-digit code, such as 126334, that tells you the model generation, the case size, the bezel style and the metal of the watch, all before you have seen it. Read the digits in three blocks: the first four identify the model and generation, the fifth identifies the bezel, and the sixth identifies the metal. Once you know that pattern, a listing that says “Datejust 41 126331” tells you at a glance that it is a current generation 41mm with a fluted bezel in Everose Rolesor. This guide explains each block, where to find the number on the watch and its paperwork, and how to use it when buying or selling in London.

Where do you find the reference number on a Rolex Datejust?

The reference number is engraved between the lugs at the twelve o’clock position, hidden under the bracelet where it meets the case, and it is printed on the warranty card that came with the watch. To read it on the watch itself, remove the bracelet end link or look closely at the gap with the bracelet flexed. The serial number sits opposite, between the lugs at six o’clock on older watches and engraved on the inner bezel ring, called the rehaut, on anything made after around 2008. The two numbers do different jobs: the reference tells you what the watch is, the serial tells you which individual watch it is and roughly when it was made.

What do the first four digits of a Datejust reference mean?

The first four digits identify the model family and its generation. On the current Datejust range, 1263 means a Datejust 41 fitted with the calibre 3235 movement, introduced in 2016 and still in production. 1262 means the Datejust 36 of the same generation. 2782 is the Datejust 31, and references starting 279, such as the 279173, are the 28mm Lady-Datejust. The previous generation also used six digits but started with 116, so a 116234 is a Datejust 36 from the mid 2000s to 2018 with the older calibre 3135. The generation before that used five digits starting 162, such as the 16234 from the late 1980s to the early 2000s. The rule of thumb is that a 126 prefix means the current generation, a 116 prefix the one before, and a five-digit number an older watch.

What does the fifth digit tell you about the bezel?

On the Datejust 36 and 41, the fifth digit describes the bezel. A zero means a smooth, domed bezel, as on the 126300 and the 126200. A three means the fluted bezel that most people picture when they think of a Datejust, as on the 126334 and 126234. On current references an eight means a bezel set with diamonds, as on the 126284RBR, where the letters RBR after the number confirm the diamond setting. The previous generation used a four for the same diamond bezel, as on the 116244, and older five-digit references used a two for the engine-turned bezel, as on the 16220, a style Rolex no longer makes. The 31mm and 28mm references use their own bezel digits, so on those sizes read the last digit for the metal and check the bezel by eye.

What does the last digit tell you about the metal?

The last digit identifies the metal. A zero is stainless steel throughout, so the 126300 and the 126200 are all-steel watches. A one is Everose Rolesor, meaning a steel case and bracelet with an Everose gold bezel and centre links, as on the 126331. A three is yellow Rolesor, steel with yellow gold, as on the 126333 and the 31mm 278273. A four is white Rolesor, steel with a white gold bezel, as on the 126334 and the 126234, which is the most common Datejust configuration in the UK. Across the wider Rolex range, an eight is solid yellow gold, a nine is solid white gold and a five is solid Everose. The 31mm references follow the same rule for the last digit, so a 278274 is white Rolesor and a 278240 is steel.