What to write in a 21st birthday card

friends cheers with an ice cold beer


The big 2-1. Think back to how excited you felt when you finally turned 21. A grown up. An adult. Someone who could legally order a drink at a bar. You know, all the things that matter most when you’re in your early twenties. For some of us, remembering that feeling is a little bit more difficult (if you’re feeling old, it’s not because I said it!), so thinking of how to tell someone happy 21st birthday might feel tough.

Everyone appreciates getting a birthday card with a personal, handwritten message. Just think about your relationship with the recipient and write something from the heart. Still feeling stuck? Don’t worry, I can help! Look below for a list of idea starters – and feel free to add your own spin to them!

How is it possible your baby is turning 21?! Yes, I agree that you look way too young to have a child that age, but that doesn’t change the fact that you need something to write in his or her birthday card.

21st Birthday Messages for Daughter

  • I’m so proud of you and everything you’ve accomplished so far.
  • No matter what, you’ll always be my little girl.
  • I can’t wait to see what the year ahead holds for you.
  • Wishing you everything special this year – because you deserve it!

21st Birthday Messages for Son

  • You’ve grown into a man I couldn’t be more proud of.
  • I can’t tell you enough how much you mean to our family.
  • I know this year is going to be amazing for you.

Whether your sibling is older or younger, sending them a 21st birthday card to let them know you’re thinking of them will make their day even more special.

21st Birthday Messages for Brother

  • I don’t say it often enough, but I’m really glad you’re my brother.
  • I’m grateful for our friendship and all the memories we share.

21st Birthday Messages for Sister

  • I love you and I’m so happy to have you for a sister.
  • I’m so lucky to have you and our friendship.

21st Birthday Message ONLY If You Are Over 21

  • Congratulations, you’re going to pay the bar tab!

Whether you’re the first or last of your friends to turn 21, you should still join in on the excitement of the day!

21st Birthday Messages For a Friend

  • YAY! You can legally drink now!
  • I can’t believe you’re finally 21.
  • Happy birthday to someone who means the world to me.
  • I’m so happy and thankful for our friendship.

Finally, Some 21st Birthday Quotes to Live By

  • “All the world is a birthday cake, so take a piece, but not too much.” George Harrison
  • “21, if truth be told, is partly young and partly old.” Unknown
  • “Birthdays are good for you, the more you have the longer you’ll live.” Unknown

Hopefully you’re feeling inspired to write your own 21st birthday message! Just remember, as long as a message comes from the heart, the person you’re sending it to will be sure to feel the love.


Hi! I’m Ashley Nard and I recently celebrated the 11th anniversary of my 21st birthday! I’ve been an editor at American Greetings since 2012. I love the color pink, watching hockey, and peppermint lattes. 

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