Flipping For These Fins

25 Mermaid Halloween Costumes For Every Sea Creature In The Fam

Pink mermaids, skeleton mermaids, The Little Mermaid...

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Halloween is inching closer, and if your kid lives for spooky season, they’ve probably known what they wanted to dress up as this year since, say, November of 2022. If they’re looking for the perfect mermaid Halloween costume, thanks to the live action The Little Mermaid release this year and renewed love for the original, there are seriously countless options for sale this year.

Some kids love mermaids for their mystical beauty, from fun-colored tresses to shiny, scaly tails. Others are mainly into the mermaid, Ariel, whether she be the ‘90s animated version with bright red hair or Halle Bailey’s live-action portrayal. And a few might like the idea of mermaids but not be totally into their usual shimmery, pastel color palette. No matter which camp your child falls into, there’s a mermaid costume out there for them.

And hey, don’t forget to dress up and have fun yourself. There are some really fun (and funny) mermaid and merman costumes for adults out this year, too. If you happen to have a baby in the family, they’d make an adorable mermaid, but perhaps an even cuter Flounder, Sebastian, or Ursula. Whichever outfits you choose, you’ll all look like you just emerged from the sea with land legs in time to start trick-or-treating.


An adaptive mermaid Halloween costume

Target’s kids' adaptive magical mermaid costume dress comes in sizes S through L, and is made with a soft, lightweight fabric for maximum comfort. Paired with some super cute seashell wheelchair covers, your little mermaid will look like they just emerged from the sea.


A costume inspired by 2023’s The Little Mermaid

If your little mermaid wants to dress up like The Little Mermaid, this kids’ Ariel costume replicates Halle Bailey’s Ariel look from the movie. It comes in 2T and 3T sizes for toddlers, as well as small, medium and large for big kids.


A skeleton mermaid Halloween costume

Is your child into the spook factor of Halloween? Scary mermaids are a thing, too! Exhibit A: the InCharacter Costumes skeleton mermaid girl’s costume from Target. This costume comes with the dress and starfish hairclip, but you supply your own shoes.


A super sparkly mermaid costume

Meri Meri has so many cute costumes that are great for playing dress-up all year long, but why not shop their collection for Halloween? This mermaid wrap costume has giant sequin scales. It fits best on kids 3 to 6 years old.


A mermaid costume inspired by Ariel

Want to dress up as Ariel from the ‘90s? Go on with your millennial self in this women’s plus size undersea mermaid costume. The top has adjustable spaghetti straps to get the right fit. One note: the wig and seaweed accessory are sold separately.


A costume for your littlest sea witch

Babies have a way of stirring up trouble, not unlike everyone’s favorite sea witch. This adorable Ursula costume bodysuit for baby includes the dress and hair headpiece. It’s available in sizes 3-6M up to 18-24M. You could also opt to dress them as Sebastian (so cute, so crabby).


A mermaid fairy princess costume mashup

If your kid asks to be a mermaid princess (but specifically not Ariel), and you wonder, ‘How the heck will we pull that off?,’ fear not. The kids’ light-up mermaid fairy deluxe costume from Party City has you covered, and it even lights up.


A mermaid costume with long sleeves

If your merkid needs longer sleeves to trick-or-treat where you live, this one has a little more mesh coverage on the arms that might help. The Rubie’s magical mermaid girl’s Halloween costume comes in a beautiful blue with lots of under-the-sea accents all over.


A classic The Little Mermaid costume for babies

Want to dress your littlest mermaid up as the animated Ariel you grew up with? This Classic Ariel costume lets babies crawl and toddle comfortable while looking adorably royal. It’s available in size 6-12M.


And one for the big kids

Straight from the official Disney Store comes this Ariel costume for kids! It comes in so many sizes (3 through 13) and also comes in an adaptive style. The shoes, tiara, and other accessories are all sold separately through the Shop Disney website.


An adaptive mermaid costume with a chair accessory

Want an adaptive costume option that’s more of a blanket style? This kids’ mermaid wheelchair costume lays easily over top of your child’s lap and doesn’t rise above the waist, so if costumes with tops present a challenge for your child, this one won’t. It also comes with a seashell to attach to the back of their seat.


A pretty pink mermaid

Does your little one wear everything in pink? Well, Halloween need not be different. This Rubie’s pink mermaid costume fits the bill, and is sized for toddlers (2T through 4T) who are ready to trick-or-treat in sea-worthy style.


A baby mermaid costume complete with a bonnet

Um, if you’re looking for the cutest baby mermaid costume ever, here you go: this Disney The Little Mermaid infant posh Ariel costume is it. The little headpiece? The bows? The ruffles? It’s just too sweet.


A purple and black mermaid costume

Not all mermaids have to be pink, purple, or blue. The Darkest Siren costume is for all the little goth girlies who want to be mermaids without giving up their dark side.


A kids’ mermaid costume with pants

Does your kid prefer wearing pants over skirts (or just want a little edge added to the usual mermaid costume)? This kids’ Mystical Mermaid costume from Spirit Halloween has a super cool flare detail on the pant legs to mimic the mermaid fin effect, but in pants. Note the very cool arm bands you know you would’ve flipped for as a kid.


A classic mermaid Halloween costume

Love, love, love the ruffly tail on this kids’ Pretty Purple Mermaid costume. The purple, green, and blue color scheme feels lightly Ariel inspired without being an exact copy of her look. The wig and boa are not included.


Another live action Ariel costume

If the live-action Ariel is what you’re after, there are so many options, including this Little Mermaid live-action deluxe Ariel costume dress. It comes in sizes 3T through 12, so if you have siblings who want to dress alike, this costume is for you.


An Ariel costume that’s easy to move in

Ariel, but with pants! This toddler Ariel costume might be a little easier for little legs to move around in. It includes the jumpsuit and headband, which is fine, because how many toddlers are actually going to keep a wig on anyway? It comes in sizes 2T, 3-4T, and a child small.


An Ariel costume that includes a wig

If your kid is the kind who wants to wear a wig through the night, here’s a costume that actually includes Ariel’s signature red locks. The Spooktacular Creations kids mermaid costume comes with the costume, wig, and headband — everything you need to pull off Ariel’s royal finest.


A pastel mermaid Halloween costume

This kids Sparkling Mermaid costume is perfect for a pastel pink and purple loving child. It’s available in sizes XS through XL, but only includes the dress, so be sure to account for your own shoes and wig, if needed.


A mermaid costume with a dramatic tail

Want a simple dress with long, trailing fins? This Hitormoon Little Mermaid costume dress is simple and sweet. You can opt for sets that include accessories like jewelry and gloves for a little extra money if your child wants the bells and whistles.


A King Triton costume

Does Ariel want Dad to be her King Triton? You’ll need this The Little Mermaid King Triton costume for men. It comes with the shirt, pants, crown, and gauntlets, so you’ll have to add the trident and beard to cart separately.


A dark mystical mermaid costume

This black and turquoise deluxe kids Mystical Mermaid costume is a fun twist on the usual princess mermaid look. It’s available in sizes small and medium, and includes the dress, headband, and choker necklace.


A topless merman costume

If the kids won’t mind seeing Dad in nothin’ but net, he’ll have the neighbors laughing in this Salty Merman costume (the name alone is *chef’s kiss*). The costume comes with the net, tail, and seaweed necklace (not the trident or wig-and-beard combo). It comes in plus sizes, too!


A dark mermaid costume with pants

A mermaid costume with pants ensures you can stroll the streets trick-or-treating with full mobility to chase down all your little sea creatures. This Dark Mermaid Siren costume will go perfectly with your goth mermaid’s chosen look.

Which mermaid look will your child choose? Whether they want to go Disney-inspired, spooky, pink, or sparkly, there’s a mermaid out there for every personality type.