Mermaid Costume Tutorial {includes no sew option!}

I've been going Halloween Costume Crazy! Most of my costumes are for boys but when I found out one of my friends wanted help coming up with a mermaid costume for her little girl I was delighted to get involved! We made the tail with pants instead of a skirt to make it easier for an active girl to do her thing without worrying about tripping or wardrobe malfunctions.


  • Seashell crown
  • Mermaid tail
    • 1 yard green sparkle poly mesh
    • Leggings that fit the child
    • 1/4 yard of light green felt
    • 1/4 yard medium green felt
    • 1/4 yard dark green felt
    • Hot glue gun and glue
    • Needle and thread (or use hot glue for no-sew option)
  • Sparkly long sleeve purple shirt
  • Starfish Necklace
    • Starfish
    • Hot glue gun and glue
    • Hemp twine


Step 1: Make the Tiara
How to make a mermaid seashell crown

Follow my tutorial: How to Make a Mermaid Seashell Crown to make the crown (it's not as hard as you think!)

Step 2: Make the tail
The completed tail will look like this:

It is built on a foundation of a pair of leggings. Green would be the ideal legging color in case one of the scales flips up but I could only find colors like pink and grey so I went with grey.

To start, cut the cuff of the leggings off at an angle like so. Be sure the longest point is still about 2 inches above where the finished cuffline should be.

Cut a piece of the sparkle poly that is 1/2 yard long and two inches taller than the top peak of the cut. I used the selvedge edge of the mesh as the bottom false hem edge.

Gather the center 6 inches or so of the tulle using a sewing needle and a running stitch (for new sew option: bunch up the center and secure with a safety pin)

Overlap the two ends and secure with a straight stitch (for new sew option: Secure with quick grab fabric glue)

Cut the top of the fabric off at at angle to mirror the angle of the leggings. Secure to the outside of the leggings using a basting stitch or hot glue.

Cut out a scale template from a piece of scrap cardboard (mine is about 1.5 inches wide x 2.25 inches long). Cut out scales in all three colors. Insert scrap cardboard into the leg to help it hold its shape. Starting at the bottom, right above where the poly mesh is attached, start to secure the scales to the leggings using hot glue 

(if you're a details person you might notice some white glue residue i nthe photos. This is because I started by using Martha Stewart Decoupage to make the leggings washable. Not a good application for this great medium. Skip the hassle. Just use hot glue - I did for the back half)

The finishing touch for the tail is to tie the remaining sparkle poly around the waist

Step 3: Top
The top is simply a long sleeve, purple sparkly t-shirt. Not only does it win modesty points but it will keep your little mermaid princess warm (because really, if you're wearing a mermaid costume with your belly sticking out, you will be COLD).

The necklace is simply a starfish hot glued to some hemp cord.


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  1. Love, love love this! I'm going to be making it for my daughter who has been begging to be a mermaid for years. I love that these are pants too. Perfect for my constantly cartwheeling gal. I'm going to jump on this and hopefully have it done in the next couple of weeks to show off and share your link


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