Under the Sea Girls Mermaid Tutu Dress and Headband Set. Holographic fish scale bodice, fluffy tulle skirt, matching mermaid headband. Ages 1 to 10 years for £28.99.
Some outfits get a polite smile when unwrapped. This one gets a gasp. The Under the Sea Girls Mermaid Tutu Dress is one of those pieces that genuinely stops children in their tracks, and that is before they put it on. The iridescent fish scale bodice shimmers as it catches the light, the layered tulle skirt is full enough to twirl in, and the matching headband with its glitter tail fin and shell accents completes a look that is total mermaid princess from head to toe.
Available in four ocean-inspired colour combinations with sizes running from 1 year right through to 10 years, this set works as a birthday outfit, a Halloween costume, a fancy dress staple, and a photoshoot dress all in one. At £28.99 for the full two-piece set, it is one of the most versatile and best-value mermaid dresses on the market.
What’s in the Set
- 1 x mermaid tutu dress with holographic fish scale bodice, layered tulle skirt, halter neck, and satin bow waist detail
- 1 x matching mermaid headband featuring a glitter tail fin, shell or starfish accents, and soft tulle decoration
The Dress in Detail
The Bodice
The top half of the dress is covered in a holographic, iridescent fish scale pattern that shifts colour as the light moves across it. It shimmers in blues, greens, purples, and golds depending on the angle, which gives it a genuinely magical quality that photographs beautifully. The bodice is sleeveless and structured, with a sweetheart-shaped neckline and a soft white cotton inner lining for modesty and comfort against the skin.
The Halter Neck and Back Tie
The dress fastens with a halter-style wide satin ribbon that ties at the back of the neck into a generous bow. This is fully adjustable, which means the dress can be loosened or tightened to fit a range of sizes and body shapes within each size band. It also makes the back of the dress look spectacular from behind, with the satin ribbon creating a dramatic focal point at the nape of the neck.
The Bow at the Waist
At the waist, a pointed satin ribbon bow is attached at the front. The ribbon ends are cut into a V shape reminiscent of a mermaid tail fin, which is a small but clever design detail that reinforces the mermaid theme throughout the dress rather than just relying on the fish scale fabric.
The Tulle Skirt
The skirt is made from multiple layers of soft tulle in a mix of ocean-inspired colours. The layers are dense enough to give the skirt a genuinely full, bouncy silhouette that holds its shape when twirling rather than collapsing flat. A white elastic waistband sits at the top of the skirt for a secure, comfortable fit, and the skirt falls to approximately knee length across all sizes.
The Matching Headband
Every set includes a mermaid-themed headband that coordinates with the dress colour combination. Each headband features a glitter mermaid tail fin at the top, flanked by shells or starfish accents, with soft tulle decoration in matching tones. The headband sits on a plain white alice band base that is comfortable to wear for extended periods. It is the finishing touch that pulls the full mermaid look together.
Available Colour Combinations
All four colour combinations use the same iridescent holographic fish scale bodice, which shifts between blues, greens, purples, and golds regardless of the tulle colour chosen. For more mermaid-inspired outfit ideas, take a look at our little girl mermaid dress guide.
Who Is This Dress For?
Parents planning a mermaid-themed birthday party: This dress was made for exactly this moment. Whether it is a first birthday or a seventh, the mermaid set gives the birthday girl something genuinely special to wear that fits the theme completely. The headband means no separate accessory shopping is needed. Take a look at our first birthday outfit ideas for styling inspiration.
Parents shopping for Halloween costumes: A mermaid costume at this price point that looks this good is a strong find for Halloween. Unlike single-use costumes that fall apart, the quality of the tulle and the adjustable tie mean this will last through a full Halloween season and come back out for birthday parties and dress-up play all year. Our Halloween costume ideas guide has more inspiration for completing the look.
Gift buyers: A full mermaid outfit including the headband, in a range of sizes, for under £30 is genuinely excellent gift value. It is a gift that gets used rather than stored. For girls aged 1 to 10 who love the sea, mermaids, or sparkly things in general, this will be a big hit.
When to Wear This Set
Size Guide
Sizing runs from S (1 to 2 years) through to 2XL (9 to 10 years). The size is based on dress length and chest measurement. We recommend measuring rather than relying on age alone, as children vary considerably. Visit our girls size guide for full measuring advice.
| Size Tag | Age Reference | Dress Length (cm) | Chest Min (cm) | Chest Max (cm) |
|---|---|---|---|---|
| S | 1 to 2 years | 45 | 45 | 50 |
| M | 3 to 4 years | 50 | 50 | 55 |
| L | 5 to 6 years | 55 | 55 | 60 |
| XL | 7 to 8 years | 60 | 60 | 65 |
| 2XL | 9 to 10 years | 65 | 65 | 70 |
Key Features at a Glance
- Full 2-piece set: mermaid tutu dress and matching headband
- Iridescent holographic fish scale bodice that shimmers in all colours
- Multi-layered fluffy tulle skirt in ocean-inspired mixed colours
- White cotton inner lining for modesty and comfort
- Adjustable halter neck with wide satin ribbon tie at the back
- Pointed satin ribbon bow at the waist with mermaid-fin shaped tails
- Matching mermaid headband with glitter tail fin, shells or starfish, and tulle
- Available in 4 colour combinations: Blue and Purple, Purple Mix, Deep Ocean Blue, Neon Pink Mix
- Sizes S to 2XL covering ages 1 to 10 years
- Suitable for birthday parties, Halloween, fancy dress, photoshoots, and themed events
- Soft and comfortable for extended wear
Product Specifications
| Set Contents | 1 x mermaid tutu dress, 1 x mermaid headband |
| Material | Cotton, tulle, polyester |
| Bodice | Holographic iridescent fish scale fabric with white cotton inner lining |
| Skirt | Multi-layered tulle, knee length |
| Closure | Adjustable halter neck satin ribbon tie |
| Waist Detail | Pointed satin ribbon bow |
| Headband | Glitter mermaid tail fin, shell or starfish accents, soft tulle |
| Colours Available | Blue and Purple, Purple Mix, Deep Ocean Blue, Neon Pink Mix |
| Sizes | S (1-2y), M (3-4y), L (5-6y), XL (7-8y), 2XL (9-10y) |
| Suitable Season | Spring, Summer, and any indoor occasion year-round |
| Gender | Girls |
| Condition | New with tag |
Care Instructions
Hand wash recommended Do not bleach Air dry naturally Do not tumble dry Cool iron on lining only if needed
k***A –
Lovely little dress
K***a –
It’s very cute, just like the photo. It’s for my 5-year-old daughter.