The USPS typically releases new holiday designs in late summer or early fall. Recent and upcoming features include:
Something for Everyone This Coming Holiday Season - Newsroom
Ongoing availability for stamps celebrating Hanukkah, Kwanzaa, Diwali, Eid Greetings, and traditional "Madonna and Child" imagery. Where to Buy
Beyond the Post Office, you can find stamps at various convenient locations:
A booklet of 20 featuring four collage designs: a holly wreath, amaryllis flowers, cardinals on mistletoe, and an evergreen branch with fruit.