The Brass Exchange has been a trombone dealer since 2010. We specialize in pre-owned trombones as well as a few new makes like Greenhoe Trombones and S.E. Shires trombones. Since we are constantly looking at serial numbers to determine instrument age we thought that we would share some of the info that we have learned and provide links to various websites that players might find useful.
Vintage and used trombones can usually be dated by serial number. Trombones will have the serial number either on the back of the hand slide or on the neck receiver where it attaches to the hand slide. Sometimes the serial number will be on both the hand slide and the neck receiver. Vintage King Trombones, H.N. White Era will often have the serial number on the tuning slide, but not always. Here are the professional model trombones that we have seen at our shop by brand/maker:
Note: Student level instruments are not listed on these resources.
Conn (before 1970) Hand slide Tennon below threads, outer hand slide (lower outer tube at the top in back), No serial on Bell section, but model number is on bell. You can find more helpful information on the Conn Loyalist Website https://cderksen.home.xs4all.nl/ConnSerialsConnBrass.html
King (Pre UMI Era) Outer hand slide two places, below cross brace and lower cork barrel. Neck Receiver, Earlier models also tuning slide. Here is a website dedicated to King trombones from the H.N. White era https://www.hnwhite.com/serialnumbers
Holton is usually on neck receiver. Holton Loyalist website: https://www.holtonloyalist.com/
Vincent Bach is on back of hand slide cork barrel, earlier models also had on back of outer hand slide, bell sections not serialized. Bach Loyalist https://www.bachloyalist.com/
This are the most commonly seen vintage brands, obviously not a complete list. We do keep an archive of sold instruments on our website here and try to photograph the serial numbers. Here is a link to the archive of previously sold trombones on our website. https://www.thebrass-exchange.com/archive-of-sold
If you have a unique or interesting trombone that you need assistance determining the age of the instrument, give us a call or send an email with a few photo's.