Thank a Mailman Day February 4th History and Pictures #ThankAMailmanDay – Happy Thank a Mailman Day images and download free photo. Thank a Mailman Day is your chance to say thanks to the guy, or gal, who delivers your mail. After all, they are there six days a week. The reliable postal worker is always there doing their job, regardless of the weather. They are a hardy lot. You’ll find some mail carriers on walking routes, wearing shorts in all but the coldest of winter days.