Mermaid Prom Dresses: Iconic Fishtail & Trumpet Silhouettes

A mermaid silhouette hugs the body through the bust, waist and hips and flares out from the knee. It's dramatic, glamorous and made to show off your shape. Our mermaid dresses include sheer corset bodices, floral appliqué, halter necklines and long slits, so you can go bold or elegant. As the fit is close, our free custom sizing means your hip and knee measurements can be built into the dress.

Mermaid Prom Dresses FAQs

Can you walk and dance in a mermaid dress?

Yes. The flare from the knee gives you room to move, and a dress made to your own measurements will be more comfortable than a standard size. Tell us if you'd like a slit for extra movement.

Which body shapes suit a mermaid dress?

Mermaid styles are often chosen to highlight an hourglass shape, but with custom sizing they can be made to fit many figures. Our guide to choosing your prom dress covers silhouettes in more detail.

What's the difference between mermaid and trumpet?

Both fit closely through the body. A mermaid flares from around the knee, and a trumpet flares from higher up the thigh, so it's a little easier to move in.


▼ Style Guide: Mastering the Mermaid Look

The Magic of the Fishtail & Mermaid Silhouette

The mermaid prom dress (also known as the fishtail dress) is the go-to choice for students wanting a red-carpet-ready look. This silhouette is famous for its fitted bodice and hips that transition into a dramatic flare. At HappyProm, our 2026 and 2027 collection includes everything from sequined mermaid gowns with long trains to off-the-shoulder trumpet dresses. It is a style that exudes confidence and elegance, making it a perennial favorite for UK Year 11 proms and senior balls.

A Custom Fit for Your Unique Curves

Because the mermaid style is so form-fitting, a perfect fit is essential. A dress that is too tight or too loose can lose its dramatic effect. That is why HappyProm offers free custom tailoring on all our mermaid designs. We handcraft your gown using your specific bust, waist, and hip measurements to ensure the "flare" starts at exactly the right point for your height. Our made-to-measure mermaid dresses provide the comfort and confidence you need to dance the night away.

High-Quality Fabrics & Fast UK Shipping

From heavy-weight satins that provide structure to stretch-sequin fabrics that move with you, our mermaid formal gowns are made from premium materials. HappyProm is a trusted UK-based prom store, offering fast delivery and affordable prices. Whether you are looking for a classic black fishtail or a trendy emerald green mermaid gown, discover the perfect fit for your milestone event today.

Show:
Sort By:
Spellbinding Glamour in Sheer Corsetry & Shimmering LaceTurn heads at your prom or black-tie gal..
£155.00 £129.00
Ex Tax: £129.00
Embody Red-Carpet Royalty in Sheer Lace Corsetry and Luminous SatinLeave an unforgettable impression..
£139.00
Ex Tax: £139.00
Make a bold statement at your next formal event with our stunning Electric Blue Sheer Corset Prom Dr..
£136.00
Ex Tax: £136.00
Step into a fairytale with our Light Blue Off-the-Shoulder Mermaid Prom Dress. This exquisite gown f..
£137.00
Ex Tax: £137.00
Embody Forest Luxury in a Sculpted Masterpiece of Sheer Corsetry and 3D FloralsTransform your next g..
£139.00
Ex Tax: £139.00
Make a grand entrance with this elegant black A-line prom dress. Featuring delicate spaghetti straps..
£155.00 £135.00
Ex Tax: £135.00
"Command the room in our Sunflower Yellow Mermaid Prom Dress. This show-stopping gown features a sle..
£117.00
Ex Tax: £117.00
Command the room in our Hot Pink Mermaid Prom Dress. This vibrant gown features a structured bustier..
£118.61
Ex Tax: £118.61
Dazzle the crowd in our Red Sequined Mermaid Prom Dress. This show-stopping gown is covered in shimm..
£138.61
Ex Tax: £138.61
Stop traffic in the color of the season. The KSP668 isn't just a dress; it’s a high-fashion statemen..
£123.00
Ex Tax: £123.00
Turn heads at your formal in our stunning Pink Mermaid Prom Dress. This elegant gown features a dari..
£102.00
Ex Tax: £102.00
Exude effortless grace in our Blush Pink Off-the-Shoulder Prom Dress. This sophisticated trumpet-sty..
£104.00
Ex Tax: £104.00
Fall in Love with Retro Romance and Modern AllureIndulge in pure evening luxury with the KSP701. Thi..
£124.00
Ex Tax: £124.00
Step into the night with confidence in our Art Deco Embellished Black Trumpet Prom Dress. ..
£128.80
Ex Tax: £128.80
Step into your own fairytale with our Cinderella meets Siren Light Blue Floral Applique Mermaid..
£117.00
Ex Tax: £117.00
Define Your Curves in Our Lilac Applique Mermaid GownMake an unforgettable entrance with the KSP632...
£138.00 £127.00
Ex Tax: £127.00
Exude timeless glamour in our Old Money Aesthetic Navy Blue Satin Mermaid Prom Dress. This soph..
£123.00 £109.00
Ex Tax: £109.00
Embrace a dreamy, ethereal look with our Enchanted Forest Sage Green Sheer Bodice Prom Dress. T..
£129.00
Ex Tax: £129.00
Dazzle the crowd in our Sparkly Sequined Indigo Prom Dress. This breathtaking gown is covered in shi..
£132.00
Ex Tax: £132.00
Illuminate the Night in Our Emerald Green Sequined GownMake a high-fashion statement with the KSP622..
£130.00 £117.00
Ex Tax: £117.00
Embody Royal Glamour in Our Plum Sheer Corset Sheath GownMake a breathtaking entrance with the KSP68..
£128.80
Ex Tax: £128.80
Command Attention in Our Jewel Tone Twinkling Lace GownEmbrace sophisticated glamour with the KSP543..
£120.00
Ex Tax: £120.00
Radiate Pure Opulence in Our Champagne Sequined Cape GownDiscover the epitome of luxury with the KSP..
£190.00
Ex Tax: £190.00
Set the floor on fire with our Red Fitted Long Prom Dress. This striking bodycon silhouette is desig..
£137.00 £117.00
Ex Tax: £117.00
Showing 1 to 24 of 66 (3 Pages)
Deals Of The Day
Sexy Sparkly Plunging V-Neck Dark Grey Prom Dress with Slit KSP491
Embrace Modern Sophistication in Our Dark Grey Sparkly GownRedefine evening glamour with the KSP491...
Special price:£95.00
Old price:£120.00
You save:£25.00
Beautiful Sunset Long Ombre Cape Prom Dresses KSP421
The beautiful long prom dresses in color same as sunset in maxi dress style, with this ombre prom dr..
Special price:£118.15
Old price:£128.50
You save:£10.35
Black Crystal Embellished Halter A-Line Prom Dress KSP541
Step Into Elegance with Our Crystal Halter A-Line GownDiscover the perfect blend of modern sparkle a..
Special price:£119.00
Old price:£140.00
You save:£21.00
Floral Embellished Sheer Corset Prom Gown - Sweetheart A-line Champagne Gold Tulle Gown KSP655
Make a dazzling entrance at your next big event with our KSP655 floral embellished prom gown. This s..
Special price:£138.00
Old price:£150.00
You save:£12.00
Lilac Purple Applique Corset Mermaid Prom Dress KSP632
Define Your Curves in Our Lilac Applique Mermaid GownMake an unforgettable entrance with the KSP632...
Special price:£127.00
Old price:£138.00
You save:£11.00
Happyprom © 2026