Serial number ranges vary significantly by year. Below are examples of starting serial numbers for classic models: International Harvester Serial Number Plates | Octane Press

International Harvester (IH) and Farmall tractor production years are identified via serial number plates located on the engine block, transmission, or front bolster. If the plate is missing, casting date codes on major components can be used to determine the year. Detailed, model-specific serial number tables are available from sources such as the Wisconsin Historical Society IH Archives Bates Corporation Wisconsin Historical Society

International Harvester tractor serial numbers are used to identify the specific manufacturing year of a machine. These lists typically show the for each year; if your number falls between two listed starting points, it belongs to the earlier year. Finding Your Serial Number

The comprehensive guide below details how to locate serial number plates, decode complex prefix codes, and reference the production year tables for popular International Harvester (IH) and Farmall models. Locating Your IH Tractor Serial Number Plate