Guild instruments manufactured after 2005 begin with a letter indicating the location of manufacture followed by the year. Guild Guitars does not have complete information regarding serial numbers of guitars built before the year 1960 due to a combination of missing documentation, data inconsistencies and employee errors.
Guild Guitars began to use a serial number system in 1965, but stopped between the years of 1970 and 1979. Guild Guitars has comprehensive serial number information about Guild instruments built between 1979 and 2005, and began using a standardized serial number system upon moving to its Tacoma, Washington, headquarters in 2005. In 2008, Guild opened a factory in New Hartford, Connecticut, leading to two possible serial number variations for instruments built after that year; instruments built in the Tacoma factory begin with the letter "T," while instruments built in the New Hartford factory begin with "N."
The second character in a post-2005 Guild Guitars serial number represents the year of manufacture, with "B" indicating the year 1998 and "J" indicating 2006. The second character progresses through the alphabet with each passing year in sequence. The third, fourth and fifth characters refer to the specific date of manufacture and the remaining characters indicate the unit number of the instrument relative to all others built that day.