• Award
    Award Winning Baby Swimwear Range
  • Van
    USA Delivery from only $7.99
  • Globe
    World's Largest Range of Baby Swimwear
  • Swimmers
    Recommended by Swim Schools Worldwide

Page Reviewed 03/10/2023

What swimwear do babies need? An age-by-age guide from newborn to 18-months

There are lots of options for baby swimwear, so it can be hard to know which outfit to choose for your kids. This guide goes back to basics, to help you decide what swimwear option is best for your baby or toddler.

In this guide we will:

  • show what options are available by different age groups
  • guide you through the most important things to look for in swimwear, by different ages
  • take a look at swim nappies and give advice on which ones are best for your child
  • explain the options available for children’s outdoor swimwear

We cover Baby Boy Swimwear Styles here

We cover Baby Girls Swimwear styles here

(We cover unisex styles in both of the guides above as well!)

If you’re not sure what size of swimwear is best for your baby, use our baby and toddler swimwear size guide as a reference. Click on the links below to find advice and suggestions for the best baby boy and girl swimwear for your baby’s age group:

All children from 0-18 months need a reusable or disposable swim diaper

Swim diapers are an essential piece of swimwear and any child who isn’t toilet-trained will need to wear one in a swimming pool. They are enforced as part of the double-layer diaper system requirement by most organised baby swimming lessons. 

There are two types of swim diaper available:

  • Disposable swim diapers
    • Worn once and thrown away
    • Look like regular diapers but don’t swell up in water
    • Are not very effective at preventing faeces from entering the pool
  • Reusable swim diapers

The Happy Nappy™ from Splash About is a reusable swim diaper with thick, soft cuffs that create a seal around your baby’s thighs and tummy to prevent any feces from escaping. The unique design features a gusset to allow for a full range of movement, without the risk of leaks. 

The Happy Nappy Duo™ offers the same reliable leak protection as the Happy Nappy™, with the added benefit of a silver lined layer that acts as a 2nd diaper, insisted upon by swim schools. This silver lining kills germs before they leave the diaper, protecting your baby and other swimmers from pathogens leaking into the pool. Both the Happy Nappy™ and the Happy Nappy Duo™ swim diapers are accepted and endorsed by USA Swim Schools. 

You can view the Happy Nappy™ range here.

Best baby swimwear for babies aged 0–3 months

The most important factors to consider for taking babies aged 0–3 months swimming are as follows:

  • Warmth—tiny babies can feel the cold easily, so you’ll want to prioritise swimwear that helps keep them warm. Check the temperature of your local pool before you go. For a baby aged 0–3 months, the pool should be heated to above 86°F.
  • Skin sensitivity—newborn babies often have sensitive skin, which can be irritated by chlorine. If your baby has a skin condition such as eczema, choose baby swimwear that will help keep their barrier cream in place.

Newborn Baby Swimming Top Tip:

Check the temperature of your local pool before you go. For a baby aged 0–3 months, the pool should be heated to above 86°F.

Babies aged 0–3 months tire very quickly so it’s unlikely you’ll be spending more than 10–15 minutes in the pool. Even though they won’t be in the pool for long, it’s important they wear the right swimwear so they’re as comfortable as possible.

What swimwear do you need for a baby aged 0–3 months?

Babies aged 0–3 months will need the following before they go swimming:

A Swim Diaper + Warm In One for babies who feel the cold (or for use in cooler pools) and have sensitive skin.
  + Baby Wrap Wetsuit folds flat for easy changing and keep babies’ torsos warm.

 

Best baby swimwear for babies aged 3–6 months

The most important factors to consider when taking babies aged 3–6 months swimming are as follows:

  • Freedom of movement—babies this age love to wriggle and it’s the perfect time to get them used to feeling the water on their arms and legs. Look for baby swimwear that allows for a full range of movement.
  • Warmth—younger babies in this age group will benefit from swimwear that keeps them warm so they can enjoy longer periods in the water.
    Babies will be able to spend a little more time in the pool at this age, so expect swimming sessions to last around 20–40 minutes. For this reason, it’s a good idea to invest in the right swimwear so they can fully enjoy their time in the water.

What swimwear do you need for a baby aged 3–6 months?

Babies aged 3–6 months will need the following before they go swimming:

Swim Diaper + Warm swimwear that allows freedom of movement—choose styles that allow your baby to have a full range of movement while keeping them warm.

 

Best baby swimwear for warmth and freedom of movement—babies aged 0-3 months and 3–6 months

Baby Wrap Wetsuit - Flat Adjustable Wetsuit

Standard swimming costumes are fine to wear at this age, but they still need a swim diaper. However, getting a tiny baby in and out of one can be tough, so choose a costume that you can lie flat and wrap around them, to make changing much easier.

Wrap-around swimsuits, such as the Splash About Baby Wrap are similar in style to a standard swimsuit but with the added benefit of being made from neoprene, a fabric used to make wetsuits. This material helps keep a baby’s core body temperature at the right level.


Warm In One Wetsuit - Warmest Baby Wetsuit

Keep your baby as warm as possible by dressing them in fleece-lined swimwear that covers their arms and legs. This will provide extra warmth and let them enjoy longer sessions in the pool. Newborn babies often have sensitive skin, so all-in-one swimwear will help protect their delicate skin by ensuring barrier creams that protect against the irritation of chlorine stay in place.

If your baby has cream for a skin condition such as eczema, you can apply this before you put on their all-in-one. This will help ensure the cream doesn’t wash off, giving your baby’s skin an extra layer of protection.

Best baby swimwear for babies aged 6–9 months and 9–12 months

The most important factors to consider for babies this age are as follows:

  • Preventing leaks—your baby will be in the pool for longer periods now they’re older, so choose swimwear with an integrated swim diaper to avoid any accidents.
  • Grip—your baby will be more active at this age, so swimwear made from neoprene is the ideal choice. This will help you hold your baby more securely and stop them slipping out of your hands.
  • Warmth—younger babies will still need extra warmth, especially in cooler pools, so choose baby swimwear which is made from neoprene, or has a thermal lining.
    Babies aged 6–9 months and 9–12 months have very similar needs when it comes to swimming.

At this age, your baby might start baby swimming classes and can stay in the water for longer. Standard swimming costumes are fine, but must be worn with a swim diaper to avoid accidents in the pool.

For peace of mind, choose baby swimwear with an integrated swim diaper, as these are designed to prevent faeces leaking into the pool. Alternatively, use a reusable swim diaper with your child’s usual swimsuit.

For more information on disposable and reusable swim diaper, read our guide to swimming diapers here.

What swimwear do you need for babies aged 6–9 months and 9–12 months?

Babies aged 6–9 months and 9–12 months will need the following before they go swimming:

 

A Swim Diaper + Swimwear with integrated swim diaper—this means you don’t have to worry about buying or packing a separate swim diaper in your baby’s swim bag.
  or Neoprene swimwear—this will give your little one extra warmth and let you grip them more securely when in the water.

 

Best baby swimwear with integrated swim diapers—babies aged 6–9 months and 9–12 months

Swimwear with integrated swim diaper
This swimwear features an integrated swim diaper with thick, soft ribs that create a seal around your baby’s thighs and tummy to prevent any faeces from escaping. The unique design features a gusset to allow for a full range of movement, without the risk of leaks.

Neoprene baby swimwear
Neoprene swimwear has many benefits, including providing insulation to help babies feel warmer in the water.

Find out more about why neoprene is the best material for baby swimwear here.

The Happy Nappy range combines an integrated reusable swim diaper with a neoprene wetsuit, making it the perfect choice for warm, leak-free swimming.

Best Swimwear with Intergrated Swim Diapers 

Happy Nappy™ Sunsuit

2-in-1 Happy Nappy Sunsuit provides UPF50+ coverage in the rash top style top with an in-built Happy Nappy for full leak protection. 


The only swim school approve swimsuit with an in-built Happy Nappy for the best leak protection. Little girls swimsuit with cute ruffle details. 

Best baby swimwear for babies aged 12–18 months
The most important factors to consider for taking babies aged 12–18 months swimming are as follows:

  • Buoyancy—swimwear with integrated floats supports babies in the water and keeps them in a more natural horizontal swimming position.
  • UV protection—swimwear with UV protection keeps kids safe when swimming outdoors.
  • Preventing leaks—some reusable swim diapers, such as the Happy Nappy, provide comfort to babies and give you peace of mind that they can enjoy a leak-free swim.
    From one year old, babies can start to wear float suits or vests in the pool. Although armbands are the first choice for many parents, swimwear with built-in buoyancy aids can help babies feel more confident in the pool and encourage them to maintain the natural horizontal position for swimming.

At this age, your baby will be old enough to enjoy swimming outdoors in summer. Make sure you protect them from the sun’s harsh rays with UV swimwear, as well as a hat, sunglasses and sunscreen.

What swimwear do you need for a baby aged 12–18 months?
Babies aged 12–18 months will need the following before they go swimming:

A Swim Nappy + Swimwear with built-in removable floats—these will help your baby stay above the water when they’re in the pool.
  or Buoyancy Vest—babies can wear a swim vest on top of their regular swimwear to help them maintain the correct position in the water when learning to swim. They can wear this instead of swimwear with integrated floats.
  or UV swimwear—if you plan to take your baby to the beach or an outdoor pool now they’re older, make sure they’re wearing special UV swimwear to protect them from the sun.

Best swimwear for buoyancy—Babies aged 12–18 months

Baby swimwear with built-in removable floats

You can remove the floats once your baby becomes more confident in the water. All of our Floatsuits have a 16-piece adjustable bouyancy system, where the floats can be removed in pairs as the child gains confidence in the water.

Best buy baby swimwear with integrated removable floats

The original Floatsuit is designed for girls with a 16-piece adjustable buoyancy system which can be adjusted as the swimmers confidence grows.

From $36.99

The Sleeved Floatsuits also have the 16-piece adjustable float system but they also have 3/4 arms and legs for extra sun coverage.

From $36.99

Best Baby Swim Vests

Go Splash Swim Vests

The Go Splash Swim Vests are designed with holidays in mind, these have floats which aren’t removable but are more compact, so they’re ideal for fitting in a suitcase for holidays. 

Swim Vest Features:

  • Voted Best Family Travel product for consecutive years in MadeForMums Awards
  • Ideal for holidays, compact, super lightweight and flat non-removable floats to make packing easier
  • Super soft binding to prevent chafing
  • Help children stay in the correct position for learning to swim and encourages water confidence
  • Learn to swim products designed to be worn under constant adult supervision

Baby swimwear essentials for swimming outdoors
Being properly prepared for a beach holiday can guarantee your children have a fantastic time while staying safe in the sun and water. Below is a guide to the essentials they will need for safe fun in the sun:

  • Wetsuits for cooler water
    Toddlers and older children can enjoy splashing about in cooler water for longer by wearing a wetsuit. Made from neoprene, wetsuits protect skin from the sun and provide added warmth for children while they explore the beach.
    Read our complete baby wetsuit guide here or view the collection here.

  • Rash tops for extra sun protection
    These UPF tops protect children’s shoulders, arms and torsos from the sun. Rash tops are suitable for babies aged six months and above and can be worn with a Happy Nappy or board shorts or over any other type of swimwear.
    You can view our full range of rash tops here and our full range of shorts here.

To find out more about the benefits of Float Jacket and Float Vests, read our guide here.