Cards are accepted year-round, and that includes Christmas and holiday cards. Personally, I usually bundle mine and send them just after Christmas, since I have the most cards then. I usually collect our birthday cards and Christmas cards during the year. I save a couple for myself every year and the rest go in a pile. Once a year, I'll cut off the front and toss out the back (because I feel like this helps them a little, although that's not required. Then, I put all the fronts in a large envelope to send via USPS. You can also send them in a flat rate box in case you have a bunch of cards to donate.