Paillard-Bolex Serial Numbers
May 11, 2007 -- Michael Tisdale
There is a misconception that Bolex cameras -- in particular, the H16 models -- can be identified by their serial number. Unfortunately this is not true.
Paillard S.A. used the same range of serial numbers for all H model cameras from 1936 to 1976; these numbers were allocated according to a production year (and in some cases, a span of years.)  The serial number on a Bolex camera is generally used only in determining its year of manufacture; the same is true for most of the pocket size and automatic 8mm models.
There are a few exceptions, however. The serial number can sometimes identify certain features and improvements not easily determined by looking at the camera body. More on that later. First, lets look at the production dates of the H model camera. By comparing the S/N on your H16 or H8 to the table below, you can determine the year in which it was made:
|7510||—||10000||1936 / 37|
|10000||—||15000||1938 / 40|
|15000||—||20000||1941 / 43|
|30000||—||40000||1946 / 47|
Locating your serial number
Depending on the model of your camera, the S/N may be located on several places: behind the bottom lens position and behind the turret plate; stamped inside the film chamber; stamped to the inside of the film chamber door; engraved on the bottom of the camera near the tripod mounting screw; engraved on the bottom of flat base cameras.
Important serial numbers (H16 and H8)
Even though serial numbers don't help you identify a camera model, the following numbers can be used to determine certain features:
S/N 76471 (H16 only)
Single tooth sprockets were adopted as standard on Bolex H16 cameras in 1952.  H16 cameras below this number had two rows of teeth on the sprockets and can only accept 2R (double perforated) film stock; these older cameras can still be modified, however. Any H16 with a S/N greater than 76471 can accept both 1R and 2R film.
< 100401 (H16) and < 97801 (H8)
Early cameras, prior to this number, have a single cam claw registration assembly and 190 degree aperture shutter (assuming no prior modification has been performed.) 
> 100401 (H16) and > 97801 (H8)
All H cameras manufactured above this number have a different pressure pad and trailing claw assembly; registration in these cameras is steadier than older models, as a result.  Cameras subsequent to this S/N are considered more desirable and practical for filmmaking, whether reflex or non-reflex.
There are many more serial numbers listed in Paillard Service and Repair manuals that indicate improvements in the design of the H16 and H8 (e.g. the metal logo plate was added at 9400, a frame counter was added from 33200 onwards, etc.) but these changes can be determined simply by looking at a camera.
Serial numbers for "pocket size" cameras
Like the H16 and H8, many of the pocket size and later model 8mm cameras shared the same serial number sequence. Paillard allocated a set of numbers for each production year; all models, from the B8 to the K1, fall into the range of numbers listed below. 
|A 10000||—||A 40000||1963|
|A 40000||—||A 43100||1964|
|B 10000||—||B 19200||1963|
|B 19200||—||B 56500||1964|
|B 56500||—||B 64200||1965|
|B 64200||—||B 66600||1966|
|C 10000||—||C 11200||1964|
|C 11200||—||C 38400||1965|
|C 38400||—||C 41200||1966|
More information on Paillard-Bolex serial numbers for cameras and projectors can be found on the individual pages of each model throughout this site. Where possible, I've given a specific number range for certain cameras as a guide to show the years in which it may have been produced.
1Bolex International S.A., "Serial Numbers and Date of Manufacture," (Ste-Croix, 1977), 3.
2Paillard Ltd., "Maintenance and Repair of the Bolex H Camera," (Ste-Croix, 1955), 3/5-H-12.49.
5Bolex International S.A., 1.