Celebrity Halloween Costumes 2021: Harry Styles, Megan Thee Stallion, Doja Cat, Billie Eilish, Justin Bieber, and More

Halloween is here again, and after 2020, celebrities are more than happy to dress up for the occasion. Even before October 31, celebrity Halloween costumes already dominate our social feeds as some of our faves don costumes to have some fun at parties and special events.

This year, celebrations started earlier as a handful of our celebs attended Doja Cat's underwater-themed birthday celebration in costume, including the birthday girl herself in a Princess Kida from Atlantis costume. Justin and Hailey Bieber were also at the bash in a couples' costume as a king and queen of the sea, while Billie Eilish went for comfort as a lobster. Hayley Kiyoko shouted out Squid Game with her costume, and Kourtney Kardashian and Travis Barker dressed as the punk icons, Sid and Nancy.

Check out some of the celebrity Halloween costumes we've gotten so far below — and, who knows, you may even find inspiration for a costume of your own!

NCT’s Taeyong and Jungwoo 

Stop everything you are doing because we will be talking about NCT's Jungwoo and Taeyong as Bella Swan and Edward Cullen for the rest of our lives. (The SM Halloween party gave us many great costumes this year, as usual, but this one definitely takes the cake.)

Ryan Destiny

Complete with bangs and a sword, Ryan Destiny channeled Uma Thurman's character from Quentin Tarantino's Kill Bill: Vol. 1 with this fierce costume.

Little Mix’s Jade Thirlwall

For their couples costume, Jade was Marge Simpson while Jordan Stephens was Sideshow Bob from The Simpsons. The Little Mix singer carried a cutout of Homer Simpson's head and shared her costume proudly with a teasing caption.

Olivia Rodrigo

With a blonde bob and blue dress, Olivia was Michelle Pfeiffer's Elvira Hancock from Scarface.

Taylor Swift

Taylor dressed up as an adorable squirrel and didn't miss the opportunity for a fun pun.

Channing Tatum and Zoë Kravitz

For their couples costume, Channing Tatum and Zoë Kravitz were Travis Bickle and Iris from Martin Scorsese's Taxi Driver.

Bretman Rock

Bretman and his adorable niece Cleo dressed up as Nezuko and Inosuke from fan-favorite manga and anime Demon Slayer (aka. Kimetsu no Yaiba.)

The Weeknd

The Weeknd completely transformed himself into Marlon Brando as The Godfather.

Rihanna

Rihanna looked so much like Gunna that the rapper even made one of her snaps his profile picture.

Barbie Ferreira

Barbie channeled Betty Boop and we are simply speechless.

BLACKPINK’s Jisoo 

BLACKPINK's Jisoo dressed up as her bandmate Lisa, which is just the cutest.

BLACKPINK's Lisa

Lisa, on the other hand, chose Squid Game as her inspiration.

BLACKPINK's Jennie

Also from BLACKPINK, Jennie relied on makeup this year and stunned with these golden snakes.

BLACKPINK's Rosé

Last but not least, Rosé chose to dress up as an adorable student.

Lil Nas X

Lil Nas X nailed his costume of Seth Powers from Ned's Declassified School Survival Guide. And, on the more sinister side, he also dressed up as Voldemort from the Harry Potter saga.

Joe Jonas and Sophie Turner

Is this what dreams are made of? Sophie Turner and Joe Jonas enlisted the help of Olivia De Jonge for this iconic costume inspired by the masterpiece that is The Lizzie McGuire Movie. Olivia was Lizzie while Joe and Sophie went as former Italian pop duo Paolo & Isabella.

Cole Sprouse

Cole Sprouse chose Attack on Titan's Eren Yeager.

Cardi B

Cardi B as Morticia Addams is everything we never knew we needed. But, in case one killer costume wasn't enough, the rapper and her daughter Kulture also matched in adorable witch ensembles. 

Janelle Monáe

Janelle Monáe's The Grinch costume could not be more perfect.

Alessia Cara

Alessia Cara chose to honor Amy Winehouse with her costume.

Charli D'Amelio

Charli and Chase Hudson chose not one but two couples costumes: Alice and the Mad Hatter and Jack and Sally from TimBurton's The Nightmare Before Christmas.

Ashley Benson 

So fetch. Ashley Benson channeled Clueless's Cher Horowitz.

Harry Styles

While taking the stage at his "Harryween" concert, the singer-songwriter put on his best Dorothy costume — complete with ruby slippers, of course. He even serenaded the crowd with "Somewhere Over the Rainbow!" We'd follow Harry down the yellow brick road any day of the year, TBH!

Kendall Jenner

Kenny's Mars Attacks look was absolutely out of this world! We wouldn't be surprised if that hairdo broke some records.

Justin and Hailey Bieber

On October 21, the Biebers attended Doja Cat's birthday celebration dressed as a king and queen of the ocean, with Justin rocking a beard and a triton a la The Little Mermaid and Hailey going for a Grecian-style dress and crystal crown. But that wasn't their only costume of the weekend! Hailey also rocked a series of Britney Spears looks (absolutely iconic), and they turned things cute as cuddly animals on Saturday night. Taking a more cinematic approach, Hailey also closed out the spooky season by recreating The Princess Diaries movie poster while Justin took on the cover of Free Guy, copying Ryan Reynold's costume and pose. (Check out their many costumes below!)

Camila Mendes & Madelaine Petsch

Cami & Madelaine never disappoint when it comes to friendship costumes, and their rendition of Velma and Daphne from Scooby Do is perfection.

Anna Cathcart

The TATB star went for an easy DIY option this year: a pumpkin helmet to transform herself into the perfect jack-o-lantern.

Hunter Schafer

The Euphoria star showed off her love of Soul Eater with this impressive Maka costume. Needless to say, she completely nailed it.

Ariana Grande

Ari enlisted the help of husband Dalton Gomez to create the eeriest old-fashioned movie poster as "Miss Creature From the Black Lagoon." Consider us fully spooked!

John Legend & Chrissy Teigen

Leave it to John & Chrissy to get the entire family involved. The commitment to this Addams family gathering is Level 10.

Yara Shahidi

Yara threw it back to last year's Grown-ish season finale with her Aaliyah / Tommy Hilfiger tribute.

Rebecca Black

The movie Saw might be nightmare-inducing, but Rebecca's version is all about the glam.

Saweetie

Saweetie went full Catwoman for this year's spooky szn, and her costume even earned Halle Berry's seal of approval!

Elizabeth Gillies

Even Gossip Girl herself would agree that Liz's Blair Waldorf costume was perfect. XOXO!

Storm Reid

We don't remember Chucky being this stylish! Storm pulled off the look with a brightly colored wig and striped turtleneck featuring a chic cutout.

Chloë Bailey

Channeling Angelina Jolie's Lola from Shark Tales, Chloë took Halloween dress-up to new heights. She showed off the costume on Instagram with the perfect caption: "She’s dangerous, supa bad. better watch out she’ll take your cash." She also later dressed up as Betty Boop.

Lizzo

BABY YODA! No one ever needs to do this costume again, cause it doesn't get better than this!!!! But Lizzo has four killer costumes. The star also recreated Kim Kardashian's iconic look from the Met Gala 2021; as a duo, she and influencer Lexo brought Dorothea and Vivian from Bébé's Kids to life; and she also dressed up as the doll from Squid Game.

Megan Thee Stallion

We know for a fact Megan Thee Stallion takes her costumes seriously. The star is no stranger to cosplay but her Halloween costume this year kicked it up a notch. For her first Halloween costume — because, yes, we expect more will come — Meg transformed into Pinhead, the notorious antagonist from the Hellraiser franchise. Later on, she channeled her inner Cruella De Vil.

Lee Yoo-mi

Squid Game's Lee Yoo-mi, who played Ji-yeong or player no. 240 in the hit Netflix series, decided to keep things close to home.

JoJo Siwa

JoJo gets an A+ for the commitment. The star dyed her hair brown to transform into her Dancing With The Stars partner Jenna Johnson. “It’s almost Halloween… So today I decided to dress up as [Jenna.] Made sure I hit every detail from HEAD to TOE!!! Literally colored my hair and painted my toes,” JoJo wrote on her Instagram. (If you want to see a more terrifying transformation from the duo, make sure to check out their performance for DWTS' Horror night!)

Doja Cat

Doja Cat looked gorgeous as Princess Kida from Atlantis: The Lost Empire, wearing a periwinkle blue crop top and matching skirt, wraparound sandals, and a glowing green stone necklace. For a Halloween party a few days later, she went as Ms. Bellum from The Powerpuff Girls and it was simply iconic.

Normani

Normani also made it to Doja's birthday party with a high-fashion take on a goldfish costume.

Hayley Kiyoko

Squid Game costumes will probably be all the rage for Halloween 2021, and Hayley Kiyoko shouted out Hoyeon Jung, rocking a Kang Sae-byeok costume, looking TV-ready in the signature green tracksuit emblazoned with 067. "Thanks for convincing me to watch, it was worth getting through the blood and I’m absolutely obsessed," she wrote.

Billie Eilish

While it might not be an A for effort, Billie looked cute and cozy in her red crustacean costume, attending Doja's party with her boyfriend, who wore a similar look.

Kourtney Kardashian and Travis Barker 

As noted by Cosmopolitan, the star-crossed lovers dressed as Sid Vicious and Nancy Spungen for the NoCap x Travis Barker House of Horrors on October 19. Travis covered up his face tattoos for the night and Kourtney rocked a curly platinum blonde wig. Similarly, the couple transformed into Edward Scissorhands and Kim from Tim Burton's famed 1990 movie.

This story has been updated.

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