• Sea Mermaid Halloween Costume Set
  • Sea Mermaid Halloween Costume Set
  • Sea Mermaid Halloween Costume Set
  • Sea Mermaid Halloween Costume Set
  • Sea Mermaid Halloween Costume Set
  • Sea Mermaid Halloween Costume Set
  • Sea Mermaid Halloween Costume Set
  • Sea Mermaid Halloween Costume Set
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Magic Tree Kids

Sea Mermaid Halloween Costume Set

Sea Mermaid Halloween Costume Set

$79.00 USD
$99.00 USD $79.00 USD
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Halloween Collection

Sea Mermaid Halloween Costume Set

For the girl who wants to be beautiful and a little bit terrifying at the same time — and refuses to choose between the two.

Beautiful, and Just a Little Haunted

Shimmering silver bones trace their way down deep black satin, from the shell-crowned neckline to the very tip of the tail. It's a mermaid who has been down in the dark water a very long time — and she has never looked more glamorous. This is the costume that makes the whole room turn around.

What's in the Set

Two pieces, one complete transformation — both arrive together.

Skeleton Mermaid DressBlack satin with glittering bone print and a tulle tail fin
Wavy Mermaid WigLong and vivid, finished with a little starfish clip

Lovingly Detailed

  • Glittering silver skeleton print running from the ribcage all the way down the tail
  • Shell-shaped neckline detail set with a dark jewel at the centre
  • Sweet flutter sleeves in soft sheer mesh
  • Fitted mermaid silhouette that opens into a glittery tulle tail fin
  • Lace-trimmed waist that divides the bodice from the tail

Why Mamas Love This

  • Spooky and pretty at once — no need to pick one or the other
  • Stands out from a street full of the same few costumes
  • Photographs beautifully, especially against a dark background
  • Perfect for costume parties, parades and Halloween nights
  • The kind of costume she'll remember being, not just wearing

What Little Mermaids Are Saying

★★★★★

"She had been asking for something 'pretty but creepy' for weeks and this was it. The silver print really does glitter under a light. Do note the tail is fitted, so she takes little steps in it — she loved that, said it made her walk like a real mermaid."

Danika R. — Perth, Australia

Size Guide

Not sure which size? Start with her age — then check the measurements below. If she's between sizes, we always recommend going one size up.

Recommended Age Size Dress Length (cm) Bust (cm) Waist (cm)
2T 100 78 57 54
3T 110 84 60 57
4T 120 90 63 60
5–6T 130 96 66 63
7–8T 140 102 69 66
9–10T 150 108 72 69
About the mermaid shape: this is a true fitted mermaid cut — slim through the hips and knees before it opens into the tail. It's made for gliding, posing and photographs rather than running about, so she'll take smaller steps than usual in it. Worth knowing if there are stairs or a long walk ahead.

All measurements are in centimetres and may vary slightly by 1–3 cm due to manual measurement. Ages are a guide only — please compare with her own measurements for the best fit. Colours may look a little different depending on your lighting and screen.

She'll come back from the party still walking like a mermaid. That's how you know it worked.

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