To read the serial numbers on Epiphone guitars, you must follow and understand the "YDDDYRRR" pattern that they use. In these eight-digit numbers, "Y" represents the production year, "D" represents the day of the year, and "R" represents the factory ranking or plant designation number.
In most cases, the serial numbers found on Epiphone guitars are found on the headstock, and the pattern they use really depends on which model and year your guitar was made. If your Epiphone was made in the '80s and '90s, there's a good chance it follows a similar, but different, pattern such as "FYYMMRRRR." The "F," in this instance, stands for the factory code, and the "M" stands for the month it was created. Make sure you know the year in which your model was made before decrypting the serial number.