Q. In our international magazine mailings, we always include the country name; however, we would like to know the correct procedure for including “USA” after the city/state/ZIP. Is there a comma after the ZIP code or not? Your assistance would greatly reduce the amount of tension/dissension among the writers and editor and proofreader.

A. There should be no comma before or after a zip code:

1427 E. 60th St., Chicago, IL 60637 USA