Monarch & Alco Delta Numbers (78's & 45's)

This site is dedicated to documenting all assigned delta numbers (△#####) found on Monarch Record Mfg. Co. and Alco pressings.

This is a working list and remains far from complete — currently 24% complete, with 82,789 entries still missing.

Each side of a 10" or 7" record was assigned its own delta number. Most 45s share the same base number, with Side B receiving an additional "-X" suffix (example: Side A △12345 · Side B △12345-X). Both sides (or all tracks on an EP) are listed on the same line.

A special thanks to the following contributors who have helped fill in missing entries: Phillip A., Martin K., Jacob L., Connie C., Joel C., Raymond D., and Christopher H. Additional thanks go to Discogs.com and to 45cat.com which provided the bulk of the data for this project. If you'd like to add a missing entry, please email me.

This list is very large and may take some time to fully load.