The story behind Rolex serial numbers
All single Rolex watch HAVE a serial number engraved in the case of the watch.

• Before 2007, the serial nr is located between the lugs at 6 o’clock (where the band connect to the case). The bracelet shall be removed in order to see the number.
• Between 2006 and 2007, Rolex began to engrave the serial number on the dial rehaut, or inner bezel, at the six o’clock position (as well as between the case lugs) on some models.
• Between 2008 and 2010, Rolex gradually ceased engraving the serial number on the case between the lugs. It will then be visible only in the innerbezel at 6 o’clock.
• From 1926 through the middle of 1987 Rolex serial number is sequential.
• From late 1987 through 2010 they added a letter at the beginning then 6 digits (R’789’678)
• Beginning spring of 2010, they change to a random numbering system. From that time there is no tool to exactly identify production date.

It’s also important to note that the serial number production year might differ from the first date of purchase stated in the certificate of origin.
It may have been stockpiled for some reason before being sold.
So it’s safe to say that the serial number provides a 1-2 year range on the age of the watch.

The chart below is helping you to find out the approximate production date of your watch according to the year.