The Guide to Gibson Factory Order Numbers

Do you have a Gibson from the 1940s or '50s? Chances are, it bears a factory order number rather than a traditional serial number.

If you have a vintage Gibson acoustic and would like to know more about it, please contact us.

Shortly after its founding in 1902, Gibson implemented factory order numbers (FONs) to identify and track their instruments. For acoustic guitars, FONs typically comprised a letter followed by a batch number, both of which were ink-stamped on the neck block inside the guitar's body. This practice was more or less followed until 1960.

Between 1932 and 1945, which many consider Gibson's golden age, the company formally alphabetized their FONs:

1935: A

1936: B

1937: C

1938: D

1939: E

1940: F

1941: G

1942: H

Following America's entry into World War II, which severely impacted companies like Gibson due to material and labor shortages, FONs were rather inconsistent. We've seen guitars from this period without FONs and we've seen some that have the FON stamped on the back of the headstock rather than the heel block. You can practically trace Gibson's wartime stress levels, as well as their postwar recalibration, in this breakdown: 

1943: 9xx - 22xx
1944: 22xx - 29xx
1945: 1xx - 10xx
1946: limited data
1947: 700 - 1000
1948: 1100 - 3700
1949: 2000s
1950: 3000 - 5000
1951: 6000 - 9000

By 1952, with their skilled workforce back home and quality materials once again available, Gibson reclaimed the top spot in American guitar-making. With this, they returned to a formal FON structure for acoustic instruments, albeit in reverse alphabetical order:

1952: Z
1953: Y
1954: X
1955: W
1956: V
1957: U
1958: T
1959: S
1960: R

While there are some examples of 1961 Gibson acoustics with a Q factory order number, these are quite rare, because the company shifted toward traditional serial numbers and have continued on that track to the present day.