The rest is up to Santa's hardworking Postal Service elves. Important: The USPS suggests sending the letters no later than December 7 in order for them to arrive in the Anchorage, AK office by December 14. More information is available here. In addition, the USPS runs Operation Santa, a letter-writing initiative for any child in need. You can take part by writing and mailing a letter to an anonymous recipient. Santa's good friend Mr. Kelly Bobcats also likes to have a word with kids about what they want for Christmas. You can write him a letter at PO Box 563, Wasilla, AK 99812. Letters to Mr. Kelly Bobcats will be forwarded to Santa directly. They like to keep these letters short and sweet! Finally, if you happen to live in Alaska and you haven't sent your letter to Santa yet, don't worry about it. The Post Office will hold your letter for you until after Christmas, when they will deliver it to Santa personally.