Farmall H serial #157,000 → falls between 1942 (137,000) and 1943 (168,000) → likely a late 1942 or very early 1943 model.
: Your tractor was built in a specific year if its serial number is equal to or greater than that year’s starting number, but less than the starting number of the following year. International Harvester Tractor Serial Number Table-
Newer models often use a 17-character VIN-style serial number that includes manufacturer, plant codes, and model year indicators. Where to Find the Serial Number Farmall H serial #157,000 → falls between 1942