Since you have already read our How to Find Your Rolex Model Number page, you already know how to find both the model and serial number on your Rolex. How is the serial number different from the model number, and what do those numbers mean? The serial number, which is located between the lugs at 6 o’clock, tells the year that the Rolex was created. It also helps to determine whether the Rolex watch is real or fake. Before 1987, the serial number consisted between 5 and 7 digits. In 1987, the production serials reached 9,999,999 and instead of creating 8 digit serial numbers, Rolex began adding a letter at the beginning of a serial number that consisted of 6 digits.