Best Adjustable Strap One-Piece Swimsuits for Girls of 2025

The Flintronic Mermaid Swimsuit is crafted from a comfortable blend of 85% polyester and 15% spandex, ensuring it feels soft against your little one’s skin. The swimsuit features adjustable shoulder straps, allowing you to customise the fit for your child, preventing any slips during wear. Its unique backless design not only adds style but also keeps your girl cool during hot summer days. With its vibrant mermaid scale pattern, this swimsuit will make your child stand out at swimming lessons, the beach, or the pool.

The imKutie One Piece Swimsuit is a delightful choice for your little girl, featuring adorable cartoon patterns of dinosaurs and fishes in bright colours, making it perfect for holiday photographs on the beach. The breathable and soft material ensures a skin-friendly and quick-drying experience, keeping your child comfortable all day long. With high stretch and adjustable shoulder straps, this swimwear offers a comfortable fit that allows for freedom of movement. It's ideal for various occasions, including swimming, surfing, and pool parties, making it a versatile addition to your child's summer wardrobe.

The Arshiner Girls Swimsuit is designed with both style and practicality in mind. Its cute ruffle lace design and adjustable spaghetti straps provide a charming look while ensuring a comfortable fit for your child. Made from high-quality fabrics, the swimsuit is stretchy, soft, and comfortable, perfect for a day at the beach or pool. Additionally, the lightweight and quick-drying material means your little one can transition from water play to dry land effortlessly, making it an ideal choice for summer fun.

The WAWSAM Unicorn Swimsuit features a delightful design with a vibrant unicorn and stars, ensuring your little one stands out at the beach or pool. Made from a breathable blend of polyester and spandex, this swimsuit is quick-drying and comfortable for all-day wear. It offers two adjustable shoulder straps, allowing you to customise the fit for your child’s comfort. Perfect for various occasions, this swimsuit is ideal for beach outings, pool parties, or unicorn-themed events, making it a wonderful gift for young girls.

The Aisyee Girls Swimsuit features adjustable straps and elegant flounces, providing a comfortable fit for growing girls. If your child is taller or a bit chubby, choosing a size up is recommended. This swimsuit is perfect for summer vacations, as it is breathable and easy to care for, ensuring your child stays comfortable during beach outings. Additionally, it is made from quality fabrics that are soft and lightweight, offering elasticity and vibrant colours that resist fading, making your girl stand out on the beach.

The Momkonzz Ruffle Swimsuit is designed for comfort and style, crafted from soft polyester fabric that feels gentle against the skin. Its fashionable halter design, adorned with playful ruffles, adds a cute touch to any beach outing. You will appreciate the adjustable straps, ensuring a perfect fit for your child, enhancing their swimming experience. Available in multiple sizes, this swimsuit caters to girls aged 7 to 16, making it a versatile choice for summer fun.

The Disney Stitch Swimsuit is perfect for your young Disney fan, allowing them to make a splash in style this summer. With a variety of sizes available, the adjustable straps ensure a secure and comfortable fit for all-day fun. The stretchy material allows for easy movement, making it ideal for active days at the beach or pool. As an officially licensed Disney product, it features a vibrant Stitch design, adding a fun touch to their swimwear collection.

The SERENYOU One Piece Swimsuit is designed with your child's comfort in mind. Made from high-quality materials, it includes 82% polyamide and 18% spandex, ensuring a silky and soft feel against the skin. The adjustable elastic shoulder straps provide a better fit, allowing for ease of movement during play. Its unique alphabet strap design adds a beach-chic touch, making your little one stand out. Additionally, the full abdominal coverage and A-line design offer both style and confidence, perfect for any summer activity.

The PythJooh Girls Swimsuit is a delightful one-piece costume designed for girls aged 4-12. Made from high-quality polyester fabric, it offers UPF50+ sun protection, ensuring your little one is safe from harmful rays while enjoying outdoor activities. The soft Polyamide material provides comfort and flexibility, allowing for easy movement in the water. With its charming 3D cartoon patterns, your child is sure to stand out and feel confident at the beach or pool. Additionally, adjustable shoulder straps ensure a perfect fit for growing girls.

The GRACE KARIN Swimsuit Set is designed for comfort and style. It features a size guide that encourages you to select based on height, ensuring the perfect fit for your child. Crafted from a soft blend of polyamide, polyester, and elastane, the fabric provides a snug yet flexible fit, making it great for all-day wear. The one-shoulder design comes with an adjustable strap, allowing for freedom of movement during swimming or beach play. The set also includes a versatile swim skirt for added coverage and ease, perfect for various water activities.