40+ happy 18th birthday messages and wishes

Turning 18 is an exciting time of life that a few of us here at thortful can just about remember. All of a sudden, you’re legally old enough to take out a mortgage, get married, vote in elections, and perhaps most importantly, buy alcohol. It’s also when you’re considered to be a fully grown adult, which is why writing an 18th birthday message for a friend or loved one is often different from the cards you gave them in previous years. But if that’s the case, then how do you know what to write in an 18th birthday card?

Since this is a very special occasion that only happens once (unlike all those other boring birthdays that slide by without any extra fanfare), we’ve put together some 18th birthday messages for you to take inspiration from or just outright steal if you like (we promise we don’t mind).

Heartfelt 18th birthday card wishes

The level of heartfeltness (yes, that’s definitely a real word) which you add to the card is totally up to you. If you’re looking for something quick and sweet to include in a cute 18th birthday card, try one of these:

  1. Congratulations on becoming a kind, funny and truly wonderful adult.
  2. Wishing you all the happiness in the world on your 18th birthday.
  3. You’ve already done so much in your life; let’s see what adulthood will bring!
  4. Happy 18th birthday to the most amazing person who ever existed.
  5. We’re so proud to have watched you transform from the cutest kid into the most beautiful adult.
  6. It genuinely makes me a bit emotional to think about you turning 18 today.

The messages above work nicely for an 18th birthday card message, but you might want to really melt their heart, in which case, make it more personal by including details of their childhood. If you’re their parent, you could tell them that their arrival in this world was the most magical day imaginable and share a memory. You could also include a mini flashback to their favourite toy as a child or something that you used to do together when they were small – feel free to be as sappy as you like on this very special occasion.

Funny 18th birthday messages

You can’t beat having a good old giggle, especially on someone’s birthday. To help you get the birthday boy or girl chuckling their socks off, we have a wide range of funny 18th birthday cards. Top it off with one of our funny 18th birthday messages that you could use inside:

  1. You’re now a mature and responsible adult. Can I borrow a tenner?
  2. We don’t mean to rush you, but isn’t it time you found your own place?
  3. You have officially reached adulthood. Each birthday from now on will make you feel that little bit older. Welcome to the club.
  4. See those tiny wrinkles next to your eyes? Prepare to start building an impressive collection.
  5. Now that you’re 18, make sure to drink responsibly. That means not forgetting to buy everyone a round.

Uplifting 18th birthday quotes

Becoming an adult when you turn 18 is a major turning point in life. It’s when many young people start truly thinking about jobs they’d fancy doing for a living, what kind of things they want to achieve, and the kind of person they will grow into over the coming years.

This is the perfect opportunity to offer them motivation and fuel their can-do attitude by including an uplifting 18th birthday quote in their card. Below are a few suggestions of quotes by famous people, and a quick Google will present countless more.

  1. “The purpose of our lives is to be happy.” – Dalai Lama
  2. “Many of life’s failures are people who did not realise how close they were to success when they gave up.” – Thomas Edison
  3. “You only live once, but if you do it right, once is enough.” – Mae West
  4. “The whole secret of a successful life is to find out what is one’s destiny to do and then do it.” – Henry Ford
  5. “Do all the good you can, for all the people you can, in all the ways you can, as long as you can.” – Hillary Clinton
  6. “Live for each second without hesitation.” – Elton John

Inspirational 18th birthday messages

A milestone birthday when you’re officially classed as an ‘adult’, turning 18 is a major deal. On their 18th birthday, why not leave them with a little food for thought with one of our inspirational 18th birthday messages?

  1. From today, every decision you make is your own. So, push yourself, be stupid and make mistakes while it’s still appropriate to do so. Hope you have an amazing 18th birthday!
  2. Wishing you all the successes in life, I can only begin to imagine the adult that you’re going to become. Happy 18th birthday!
  3. As you enter the next stage of life, it’s not always going to be easy, but I know that you’re going to go on to amazing things.
  4. Today is all about celebrating your 18th birthday and getting excited for all the things that you’re going to experience over the years.
  5. Sending you the happiest 18th birthday wishes, remember that you’re in control of your own life and can achieve anything you want with hard work.

Happy 18th birthday wishes for your son

Writing a card for your son can be difficult, as you may not want to come across as too schmaltzy, but at the same time, you need him to know just how much he means to you. This is also a milestone birthday that separates adolescence from manhood, so you’ll want to strike the right balance.

What you write in your son’s 18th birthday card is, of course, entirely up to you, but here are a few ideas of happy 18th birthday wishes for your son that may help.

  1. Happy birthday, son. Not a day goes by that we don’t feel proud of who you are and what you do for others around you.
  2. Our tiny bundle of joy is now a tall, hairy man who leaves the toilet seat up. Despite the smelly socks, we love you more each day!
  3. Whenever you’re having a hard time or doubting yourself, all you have to do is talk to us, and we’ll remind you how caring, resilient and incredible you really are.
  4. Our baby boy is now an intelligent, creative, and capable young man. We couldn’t be more proud of you if we tried.
  5. No matter what you do in life, we’ll always be here to cheer you on, offer support and help you in any way we can. We love you so much and wish you the happiest 18th birthday in history.

Sweet 18th birthday messages for your daughter

If it’s your daughter’s 18th birthday, you can get a bit soppier with your 18th birthday card messages. Here are a few suggestions for sweet 18th birthday messages for your daughter that she’ll never forget.

  1. Here’s to our fabulous daughter on her 18th birthday. May the bubbles flow freely and the dancefloor never empty!
  2. On this very special day, we just want you to know that we will always love you with all our hearts and never stop being here for you.
  3. Our darling daughter is now a beautiful young woman. Wishing you all the happiness in the world on your special day.
  4. You may be an adult, but you’ll always be our little girl. However, we’re still not getting you a pony.
  5. We’re so proud of the strong, independent young woman you’ve become. Now, get out there and smash the patriarchy!

18th birthday messages for a friend

Regardless of whether you’ve been inseparable since childhood or have recently developed a close friendship over the last few years, if you’ve got a mate about to turn 18 then it’s time to celebrate.

Remind them of a memory only the two of you laugh about or their most embarrassing moment, if you’ve no clue what to say then our 18th birthday messages for a friend aren’t a bad option either.

  1. It’s your 18th birthday bestie! You’re a bad b*tch and I can’t wait to pop the bottles with you later, welcome to adulthood.
  2. We’ve pretty much known each other since birth but look at us now – 18 and ready to take on the world. Happy 18th mate!
  3. Today might be your 18th birthday however we both know that you’re still a proper child inside. Happy birthday!
  4. Now might seem like the right time to bring up that time when you… well, I won’t go into that since you know all of my secrets too. I’ll just leave it at a happy 18th birthday bud!
  5. I’m so lucky to be able to call you my friend and can’t believe we’re actually classed as adults now, wishing you the happiest 18th birthday ever!

Sincere 18th birthday messages for your niece or nephew

Now, we’ve talked about happy 18th birthday wishes for your son and daughter, but what about the other young ones in your family like a niece or nephew? Remind them just how awesome of an aunt or uncle you are by sending them a card (and present, of course) along with a personal note inside. If you need a little assistance, our sincere 18th birthday messages for your niece or nephew will do the trick.

  1. As I never had any children of my own, it’s been amazing to watch you grow up into the 18-year-old that you are today. Happy birthday!
  2. Happy 18th birthday! Time to start living your own life and going out on adventures, we’ll always be here if you need us.
  3. It only seems like yesterday that my sister/brother came home with you from the hospital and look at you now. Happy 18th birthday!
  4. Wishing you a very happy 18th birthday! Thinking of you officially being an ‘adult’ just makes me feel so much older.
  5. Sending big birthday wishes to my niece/nephew on your 18th birthday, what a milestone!

Hopefully, you’ve now got plenty of inspiration for what to write in an 18th birthday card that they’ll treasure. Of course, these are just suggestions, and when it comes to 18th birthday greetings messages, you can always go your own way for something entirely unique.

Mind you, even the best-written 18th birthday message in the world won’t matter without a suitable card. Here are a few of our favourites:

Whether you’re looking for a card that’s funny, cute, classic, or traditional, and no matter what your relation to the recipient, check out our wide range of 18th birthday cards. And don’t forget that they’re now allowed to celebrate with a cheeky tipple, so why not send them some one of our alcoholic gifts to go along nicely with their card? We know just how hard it can be to come up with new messages for every special occasion which is why we’ve created all sorts of what-to-write guides over on our blog.