The codes that appear in columns F and J (see picture below) of the 1940 U.S. Census
have been summarized in a
1940 Census Bureau publication
These codes were put on the census pages well after the
enumeration was done, and therefore provide no additional information. However, sometimes
knowing the code can help you determine the occupation in cases where the quality of the
microfilm is poor or the handwriting of the enumerator is difficult to read.
To decipher the information, enter the three codes from column F or column J in these boxes.
1940 census column F