National Thank A Mail Carrier Day February 4th reminds us that someone makes sure the mail gets through 6 days a week 52 weeks a year. A note of just how important mail carriers are to our daily lives. Take time out of your day to thank the mail person who is responsible for delivering your mail to you. The motto of the Pony Express riders, who were the most famous early American mailmen, was “Neither rain or snow nor death of night, can keep us from our duty.” Mailing letters.