Girl sitting on a white bed wrapped in a pink crochet mermaid tail blanket with a textured fin.

Crochet mermaid tail blanket pattern

I’m thrilled to share my new Crochet Mermaid Tail Blanket Pattern with you! This pattern is designed for three sizes: child, teen, and adult. It’s perfect for anyone who dreams of being a mermaid. So grab your yarn and hooks, and let’s start creating this enchanting blanket together!

Crochet mermaid tail blanket pattern details

Here’s a quick overview of the materials, sizing, gauge, and pattern notes before you begin.

Skill level

Advanced beginner. This pattern uses basic crochet stitches with some shaping.

Materials needed

  • Crochet Hook Size: M/N-13 9 mm
  • Yarn: Worsted weight yarn. I used 4 skeins (7 oz/198 g) or Red Heart Super Saver in the color Flamingo.
  • Yarn needle: Use this to weave in your ends.
  • Scissors: Use scissors to fasten off your yarn.
  • Stitch marker(s): Optional. Use these to help keep track of your stitches. 

Finished size

SizeWidthTotal Length
Child16.5 inches54 inches
Teen17.5 inches58 inches
Adult18.5 inches62 inches

Gauge

11 stitches and 8 rounds = 4 inches (5 cm)

Crochet abbreviations

  • dc = double crochet stitches
  • hdc = half double crochet
  • blo = back loop only
  • ch/chs = chain/chains
  • ch sp = chain space
  • st/sts = stitch/stitches
  • sl st = slip stitch
  • rnd/rnds = round/rounds
  • rem = remaining

Pattern notes

  • The pattern is worked in the round from the bottom up.
  • You will make the tail section first and then add the fin.
  • Repeat instructions between the asterisks (*) for the rest of the round.
  • The pattern is written in US terms.
Girl sitting on a white bed wrapped in a pink crochet mermaid tail blanket with a ribbed textured fin.

Crochet mermaid tail blanket pattern instructions

Rounds 1-27 are the same for all sizes.

Mermaid tail instructions

Rnd 1: Magic Ring, ch 2, 6 dc, join. (6 stitches)

Rnd 2: Ch 2, 2 dc in each st, join. (12 stitches)

​Rnd 3: Ch 2, dc in each st, join. (12 stitches)

Rnd 4: Ch 2, *2 dc, dc in next st, repeat from * around, join. (18 stitches)

Rnd 5: Ch 2, dc in each st, join. (18 stitches)

Rnd 6: Ch 2, *2 dc, dc in next 2 sts, repeat from * around, join. (24 stitches)

Rnd 7: Ch 2, dc in each st, join. (24 stitches)

Rnd 8: Ch 2, *2 dc, dc in next 3 sts, repeat from * around, join. (30 stitches)

Rnd 9: Ch 2, dc in each st, join. (30 stitches)

Rnd 10: Ch 2, *2 dc, dc in next 4 sts, repeat from * around, join. (36 stitches)

Rnd 11: Ch 2, dc in each st, join. (36 stitches)

Rnd 12: Ch 2, *2 dc, dc in next 5 sts, repeat from * around, join. (42 stitches)

Rnd 13: Ch 2, dc in each st, join. (42 stitches)

Rnd 14: Ch 2, *2 dc, dc in next 6 sts, repeat from * around, join. (48 stitches)

Rnd 15: Ch 2, dc in each st, join. (48 stitches)

Rnd 16: Ch 2, *2 dc, dc in next 7 sts, repeat from * around, join. (54 stitches)

Rnd 17: Ch 2, dc in each st, join. (54 stitches)

Rnd 18: Ch 2, *2 dc, dc in next 8 sts, repeat from * around, join. (60 stitches)

Rnd 19: Ch 2, dc in each st, join. (60 stitches)

Rnd 20: Ch 2, *2 dc, dc in next 9 sts, repeat from * around, join. (66 stitches)

Rnd 21: Ch 2, dc in each st, join. (66 stitches)

Rnd 22: Ch 2, *2 dc, dc in next 10 sts, repeat from * around, join. (72 stitches)

Rnd 23: Ch 2, dc in each st, join. (72 stitches)

Rnd 24: Ch 2, *2 dc, dc in next 11 sts, repeat from * around, join. (78 stitches)

Rnd 25: Ch 2, dc in each st, join. (78 stitches)

Rnd 26: Ch 2, *2 dc, dc in next 12 sts, repeat from * around, join. (84 stitches)

Rnd 27: Ch 2, dc in each st, join. (84 stitches)

Child size

Rnds 28-108: Ch 2, dc in each st, join. (84 stitches)

Fasten off and weave in your ends.

Teen size

Rnd 28: Ch 2, *2 dc, dc in next 13 sts, repeat from * around, join. (90 stitches)

Rnds 29-116 : Ch 2, dc in each st, join. (90 stitches)

Fasten off and weave in your ends.

Adult size

Rnd 28: Ch 2, *2 dc, dc in next 13 sts, repeat from * around, join. (90 stitches)

Rnd 29: Ch 2, dc in each st, join. (90 stitches)

Rnd 30: Ch 2, *2 dc, dc in next 14 sts, repeat from * around, join. (96 stitches)

Rnds 31-124: Ch 2, dc in each st, join. (96 stitches)

Fasten off and weave in your ends.

Adding the fin

The fin pattern is the same for all sizes. 

Join your yarn between rounds 14 and 15.

crochet mermaid tail

Ch 1 and make a sc in the same space. Work towards the tip of the tail.  Sc in the side of each row and in the chain space between each row. 

Slip stitch in the point of the tail and mark with a stitch marker.

Continue to sc up the opposite side, ending between rows 14 & 15. (28 stitches on each side = 56 total stitches)

← Working away from the tail

​→ Working towards the tail

← Row 1: ch 58 (58 chains)

→ Row 2: hdc in the 3rd chain from the hook and in each rem ch, join with a sl st to the next stitch on the tail, turn (56 stitches)

← Row 3: ch 2, hdc blo to the second to last st, leave the last st unworked, turn

→ Row 4: sl st in the first st, hdc blo in the next st and in each rem st, join with a sl st to the next sc on the tail, turn

← All odd numbered rows (5-53) are working away from the tail: repeat row 3

→ All even numbered rows (6-54) are working back towards the tail: repeat row 4

​Rows 1- 54 will each decrease by one stitch.

Skip over the middle stitch at the tip of the tail. You should have marked it with a stitch marker.

← Row 55: ch 2, hdc blo to the second to last st, 2 hdc blo in the last st, turn

→ Row 56: 2 hdc blo in first st, hdc blo in each rem st, join with a sl st to the next sc on the tail, turn

← All odd numbered rows (57-105) are working away from the tail: repeat row 55

→ All even numbered rows (58-106) are working back towards the tail: repeat row 56

Rows 55- 106 will each increase by one stitch.

Finishing

Fasten off and weave in your ends. 

PDF version

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lovable loops free crochet mermaid tail blanket pattern

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Let’s connect!

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📌 Don’t forget to pin this pattern for later!
Happy crocheting! 🧶
— Melissa

Pinterest pin for a free crochet mermaid tail blanket pattern, showing a girl wrapped in a pink mermaid tail blanket on a white bed.