Credit: Eric Charbonneau/

Jennifer Aniston and Justin Theroux have reached another relationship milestone: mailing out their first joint holiday card!

The red Christmas greeting, which was obtained by Lainey Gossip, reads: "We wish you and your family a holiday season full of happiness and joy. A donation has been made in your name to St. Jude Children's Research Hospital and Best Friends Animal Society."

Aniston -- who has been a longtime supporter of both non-profit organizations -- signed the card, "With warmth and love, Jen and Justin."

Though they've been joined at the hip since taking their relationship public in June, Aniston, 42, has no immediate plans to marry her Wanderlust costar Theroux, 40.

"I've been married once, and I don't know if I'll get married again," she said in October. "But I can tell you that as of this moment, I have no plan to get married. Got that?"