21st Birthday Theme Ideas: 13 Ways to Plan the Party of the Decade

Turning 21 is a big deal! Whether you’re planning a surprise party for a friend or looking for ideas for your own special milestone, there are lots of ways to celebrate. From birthday trips to drink-inspired activities and classic pool parties, you can choose conventional or trendy ideas to honor the big moment. 

We’ve put together this list of 21st birthday theme ideas so you can pick the perfect one to reflect the guest of honor’s interests, hobbies, or favorite activities. Pick one theme or mix and match a couple for the perfect celebration.

13 of the Best 21st Birthday Theme Ideas

Looking for memorable ways to celebrate 21 spins around the sun? Ths list of 21st birthday theme ideas has what you need to pull off the party of the decade. They’re sure to take your party to the next level and have people talking about the festivities for years to come.

1. Las Vegas Themed Party

No list of 21st birthday party ideas is complete without mentioning Las Vegas. Long the destination of choice for people who’ve reached the legal drinking age, you can choose to head to Sin City for a weekend or bring Vegas vibes to a house party.

For a Las Vegas trip, invite all of your friends to stay at the same hotel and hit up pool parties, nightly DJ sets, and world-class shows and residencies while you’re in town. Be sure to mention it’s your birthday to get freebies at most spots. Make it a road trip and check out natural attractions near Vegas including the Red Rock Canyon National Conservation Area.

If you’re staying home, bring the Vegas vibes in with a casino night party. Set up tables and play games like blackjack and poker. Don’t forget to have some festive cocktails and enjoy being 21!

2. Go to a Drag Brunch

Design: Blustery August

Who doesn’t love a brunch party? They’re packed with mimosas, tasty treats, and good vibes galore. Take your b-day brunch up a notch with a visit to a local drag brunch. You and your party guests will be entertained by drag performers in sequins, belting out popular tunes, and performing hilarious skits. It’s the perfect way to celebrate 21 fabulous years on the planet.

3. Famous Star Party

Celebrate like the rich and famous with a party dedicated to your favorite star, whether it’s Taylor Swift, Beyoncé, or Leonardo DiCaprio. Make it a Hollywood costume party and ask guests to dress up as the famous star in one of their eras, movies, TV shows, or music videos. 

For 21st birthday decorations, roll out the red carpet and decorate the room with Hollywood motifs like movie reels, golden awards, and metallic balloons. 

And if you’ve chosen a musician as your inspiration, make it an unforgettable night and have a karaoke competition singing their songs for extra flair. 

4. Coachella Party

Bring the vibes of good music to your big day with a Coachella-themed 21st birthday party. Invite your best friends and turn your backyard into a mini Coachella set. You can hire a local DJ to spin sets or just curate a playlist of the biggest hits from the latest music fest.

Ask guests to dress their best and hire entertainers to keep the fun going all day long. You can have a body painter, tarot card reader, and live band to entertain friends. Don’t forget to serve up Instagram-worthy food and get a bartender to whip up drinks to fuel the fun.

5. Barbie Party

Based on the trending movie, this 21st birthday celebration theme is a fun way to celebrate an out-of-this-world milestone. Plus, it’s easy to DIY the party decorations because the color pink takes center stage. Deck out the room with pink balloons, pink tablecloths, and glam accents like metallic confetti and sequins. 

Set up a photo booth where guests can make memories and take pictures together. Don’t forget props and Barbie accessories like sunglasses, crowns, and fashionista items including lipstick, shoes, and glittering jewels. 

6. Glamping Slumber Party

Celebrate your special day with laid-back vibes by hosting a glamping sleepover. You won’t be roughing it in the woods with this 21st birthday party theme. Instead, book glamping tents or cabins to keep everyone comfortable. Deck out each room with a special gift basket including bug spray, cozy pajamas, and night sky books. Spend time looking for constellations and sip themed drinks like a toasted s’mores martini.

7. Roaring 20s Masquerade Party

Get ready for a night of mystery with a Great Gatsby-inspired masquerade party. Decorate the space with gold and black decor including art deco geometric shapes. For a luxurious feel, set up several small lounges and seating areas with plush velvet furniture. 

Ask guests to dress in their best roaring 20s attire including flapper dresses, bold jewelry, and beaded headpieces. Keep guests dancing late into the night with jazz, blues, and swing music. To make the special day even better, serve up Prohibition-era cocktails like old fashioneds and mint juleps.

8. Boho Spa Day

Design: Claudia Owen

Get your closest friends together for a low-key 21st birthday celebration that isn’t about partying late into the night. Book a full day at a local spa to get facials, massages, and manicures. Make the day memorable by giving each guest a monogrammed bathrobe or spa tote bag. If you don’t want to splurge, you can plan an at-home spa day where you pamper yourselves with face masks and foot soaks instead.

9. Pool Party

Obsessed with having fun in the sun? Plan a pool party to celebrate turning 21! Make it a retro-themed bash by handing out cat-eye sunglasses and flowered shower caps or keep it modern with floaties in the shape of unicorns, llamas, and flamingos.

Stay cool and refreshed now that you’re of legal drinking age with classic pool cocktails including piña coladas and daiquiris. Keep guests fed during the day with a BBQ cookout featuring classics like hot dogs, burgers, and grilled veggies.

10. Escape Room

Design: Claudia Owen

Do you love party games and being competitive? Plan your 21st celebration at an escape room. Most of these businesses offer several different themes so you can pick one that matches your personality. Make it a full day of fun by booking a party bus to pick up all of your friends, bring them to the escape room, and then head to celebratory drinks after.

11. Take a Mixology Class

Another fun 21st birthday party theme idea, a mixology class is a great way to celebrate the birthday star while also learning about the world of alcohol. Hire a professional mixologist to teach you how to combine flavors and create craft cocktails based on your taste preferences. It’s the perfect way to find your signature drink or discover which types of drinks you enjoy — whether they’re alcoholic or non-alcoholic versions.

12. Fiesta Time

One of our favorite 21st birthday theme ideas, this fiesta-inspired idea is all about vibrant colors and delicious foods — and it’s SO festive! Set the scene with colorful textiles featuring vibrant stripes. Papel picado banners and balloons in bold hues are the perfect addition. 

Serve up delicious foods like tamales, tacos, and tostadas. Don’t forget a few adult beverages like margaritas or arrange for a tequila tasting to celebrate the big 2-1.

13. Host a Scavenger Hunt

If the birthday honoree is playful, consider planning a 21st birthday-themed scavenger hunt. Plan an evening out on the town and print a list of actions everyone needs to do or things they need to find. Some ideas include: 

• Order a pink drink
• Take a shot with a stranger
• Take a photo with a bartender
• Ask the DJ to play a specific song
• Find a funny bar napkin

At the end of the hunt, celebrate by diving into some birthday cake!

Plan an Unforgettable 21st Birthday Party

With these 21st birthday theme ideas, you’re sure to plan a memorable celebration for this milestone year. Once you know how you want to celebrate, head to Greenvelope and pick out a 21st birthday invitation. Each template is customizable so you can make it unique by changing the color scheme, switching the font, or uploading a photo.

For more party planning tips, continue browsing our Stationers blog. You’ll find tons of ideas from party themes and decor to food and activities to keep the fun going. Be sure to check out our list of 21st birthday party ideas for more inspiration on how to spend your special day.