If you are sending cards, packages, or other material through the U.S. Postal Service (UPSP), watch for deadlines so your items arrive by December 25. The USPS posted these deadlines for states other than Alaska and Hawaii (which have different schedules): December 16 for USPS Ground Advantage Service and first-class mail (including greeting cards), December 18 for First-Class Mail service, December 19 for Priority Mail Service, and December 20 for Priority Express Mail. Note: The Postal Service is the only delivery service that ships to APO, FPO, and DPO addresses. #IdeaoftheDay