According to the Mirror, there’s just one small requirement you need to fulfill—and your location doesn’t matter. Whether you live in the UK or anywhere else in the world, you’re eligible.

How to Get a Christmas Card from the Royal Family
Many people have only recently discovered that by sending holiday greetings to certain members of the Royal Family, you can receive a personal Christmas card in return.
A mum on Instagram shared that getting a Christmas card from “a real-life princess” has become a cherished annual moment for her daughters. As long as you use proper postage, your letter should reach the palace without issues.
If you haven’t sent one yet, now is the time. The process is simple: send your own Christmas card—with a greeting or a short personalized message—and include your return address. In response, the royals will send back a pre-printed thank-you note along with a photo.
Where to Send Your Christmas Greetings
To request a card from Prince William and Kate Middleton, send your Christmas greeting to:
TRH The Prince & Princess of Wales
Kensington Palace
London
United Kingdom
W8 4PX
To write to King Charles and Queen Camilla, address your card to: