Established in 2005
If you are sending your own holiday Care Packages, cards, and letters to your servicemember, the US Postal Service encourages you to mail your items early for the holiday season. The 2020 USPS holiday deadlines for shipping items are listed below according to APO/FPO/DPO zip codes.
2020 USPS holiday deadlines:
If you wish to send your own personal packages to loved ones abroad, the USPS offers a discounted price of $18.45 on its largest Priority Mail Flat Rate Box. This price includes a $1.50 per box discount. These Flat Rate boxes are available at no cost at local Post Offices and online at shop.usps.com. For convenience, postage, labels, and customs forms can be printed online anytime using Click-N-Ship at usps.com/ship.
Source: Military Postal Service Agency