Main Menu

Costume Onesies

1 - 47 of 47

Onesies aren’t just for babies anymore—our Halloween onesies are cozy, fun, and made for everyone! From Pokémon to Winnie the Pooh to pajama-style kigurumis, we've got looks for toddlers, kids, adults, and plus sizes. Whether you're after cute or funny Halloween onesies, comfort is guaranteed. Skip the itchy costumes and shop our selection for the comfiest Halloween ever!
read moreread less
Main Content
Kids Glow in the Dark Skeleton Costume Onesie 1
Sale - 17% Made By Us
Original Price $29.99 Sale Price $24.99 
Sesame Street Kids Cookie Monster Onesie
Sale - 20%
Original Price $49.99 Select Sizes on Sale. Prices range from $39.99 to $49.99 
Super Mario Bros Boys Mario Onesie
Sale - 20%
Original Price $49.99 Select Sizes on Sale. Prices range from $39.99 to $49.99 
Kids Cozy Octopus Onesie Alt 1
Made By Us Exclusive
Kids Fleece Fly Onesie Alt 1
Sale - 17% Made By Us
Original Price $29.99 Sale Price $24.99 
Toddler and Kid's Green Triceratops Onesie
Sale - 38%
Original Price $39.99 Sale prices range from  $24.99 to $29.99 
Kids Ariel the Alligator Onesie Costume 1
Sale - 36%
Original Price $24.99 Sale Price $15.99 
Kids SpongeBob SquarePants Costume Onesie
Sale - 20%
Original Price $49.99 Select Sizes on Sale. Prices range from $39.99 to $49.99 
Kid's Disney Jack Skellington Onesie Costume
Made By Us Exclusive
Prices range from $69.99 to $99.99 
Kids Axolotl Costume-update
Video
Made By Us Exclusive
Prices range from $39.99 to $49.99 
Super Mario Bros Boys Luigi Onesie
Sale - 20%
Original Price $49.99 Sale Price $39.99 
Pokemon Child Charizard Kigurumi
Sale - 36%
Original Price $69.99 Sale Price $44.99 
Toddler Black Cat Onesie
Made By Us Exclusive
Toddler Disney Jack Skellington Onesie Costume
Made By Us Exclusive
Kids Jack o Lantern Onesie Costume
Sale - 80% Made By Us
Original Price $39.99 Select Sizes on Sale. Prices range from $7.99 to $29.99 
The Grinch Jumpsuit Costume Kids
Sale - 33% Made By Us
Original Price $59.99 Select Sizes on Sale. Prices range from $39.99 to $59.99 
Kids Disney Oogie Boogie Costume Onesie
Made By Us Exclusive
Toddler Yellow Duck Onesie
Made By Us Exclusive
$29.99 
Toddler Disney Oogie Boogie Costume Onesie
Made By Us Exclusive
Frog Infant Onesie Costume UPD 1
Sale - 25% Made By Us
Original Price $39.99 Sale Price $29.99 
Kids Ghostbusters Slimer Costume Onesie
Made By Us Exclusive
Kid's Elf Onesie Costume
Sale - 60% Made By Us
Original Price $39.99 Select Sizes on Sale. Prices range from $15.99 to $39.99 
Pokemon Kids Sylveon Kigurumi
Out of Stock
Pokemon Piplup Child Kigurumi
Out of Stock
Toddler and Kid's Cotton Candy Unicorn Onesie
Out of Stock
Espeon Child Pokemon Kigurumi
Out of Stock
Kids Pokemon Jigglypuff Kigurumi
Out of Stock
Kids Blob Fish Costume
Out of Stock
Made By Us Exclusive
Kids Rilakkuma Kigurumi
Out of Stock
Filter

Let’s be honest—babies don’t have a monopoly on being cozy and adorable. Why should the under-3 crowd get all the good onesies? We say: reclaim the zipper-front fluff life! Halloween is the perfect time to embrace your inner lounge monster, and our Halloween onesies are here to prove that comfy and costume-y can absolutely coexist. We’re on a mission to normalize adults waddling around like Pikachu in public, and frankly, we think we’re crushing it.

Our onesie lineup is like a warm hug from your favorite cartoon character. Want to be a Pokémon but also nap-ready? Boom—Pokemon onesies. Looking to channel the ultimate snack-loving bear? We've got Winnie the Pooh onesies softer than a honey-glazed dream. Prefer your Halloween look a little more "bedtime chic"? We carry pajama costume onesies that turn heads and turn in early. From spooky to silly, we’ve curated styles for every kind of Halloween vibe—and they’re all maximum comfort, minimum effort.

It doesn’t matter if you’re a toddler just learning the power of the costume, a kid ready to dominate the neighborhood candy circuit, or an adult embracing the magic of mobility and warmth—we’ve got sizes for everyone. That includes plus sizes and a great variety of kigurumis (AKA the Japanese art form of turning comfy into cosplay). You could literally throw a family Halloween party with everyone dressed in onesies, and it would be the softest, most huggable costume moment in history.

So if you're tired of wigs, tight waistbands, and peeling fake blood, it's time to zip into a cozier Halloween. With funny Halloween onesies, cute classics, and cozy critter designs galore, you'll actually want to keep your costume on all night. Shop our selection of adult Halloween onesies, kids Halloween onesies, and more—your body (and your couch) will thank you.

HalloweenCostumes.com Monster