First things first, why use swim diapers at all? As a first time parent you may not be be aware that if you want to take your baby swimming, a regular diaper will not do!

Regular diapers are designed to absorb water, and will therefore suck water from the pool into the diaper, causing it to swell and become heavy. This not only means it will not work to hold in any accidents, it will be uncomfortable and could become a drowning risk.

Do swim diapers hold in pee/urine?

A swim diaper, whether disposable or reusable, will not hold water. This of course means they won't hold in urine, but they also won't swell and cause discomfort whilst in the water. Many first time users are not aware of this and are alarmed when pee leaks from the diaper on the way to the pool Swim diapers should only be put on just before you get into the pool and should be changed as soon as possible after a fecal accident. There are currently no waterproof swim diapers on the market.

Does my baby need a swim diaper?

A swim diaper is required by all swimming pools for any child who isn't potty trained. Finding the right swimming diaper for your baby can seem like a minefield, so we have devised this in depth guide to swim diapers to help you avoid the inconvenience and embarrassment of your child having an accident in the water.

How do Swim Diapers Work?

Swim diapers are specially designed for babies and toddlers to wear while swimming. Unlike regular diapers, they do not absorb water. This prevents pool water from soaking in, which would cause the diaper to swell, become heavy, and potentially uncomfortable, unsafe, or ineffective.

Swim diapers are made to contain solid waste (like poop) but do not absorb liquids (like pee). They have a snug, secure fit around the waist and legs to help prevent leaks. This close fit helps trap solids until the diaper can be changed.

This guide features:

• Disposable and reusable swim diapers comparison chart
• Swim Diaper Size Guide
• 5 Top Tips for using a swim diaper
• How many swim diapers do I need?
• Swim diaper FAQs

Disposable and reusable swim diapers comparison chart

• A disposable swim diaper looks like a regular diaper and is worn once and thrown away
• A reusable swim diaper looks like a
  regular pair of swimming shorts or forms part of a swimsuit and can be worn multiple times

Swim Diaper Size Guide

Disposable swim diapers come in set sizes similar to standard diaper sizes – most brands sell diapers in the following sizes:

• 2-3 (to fit babies who weigh approx. 3-8kg)
• 3-4 (to fit babies who weigh approx. 7-15kg)
• 5-6 (to fit babies who weigh approx. 12-18kg)

These numbers refer to the diaper size and not the age of the child, so choose a size similar to your child’s regular diaper. Choose a snug but comfortable fit to minimize the risk of leaks.

Some disposable swim diapers designed for smaller children have adjustable tabs for a more secure fit. 

Reusable swim diapers are sized in age ranges – 0-3 months, 3-6 months, 6-12 months and so on. Your child’s age should be used as a guide for buying a reusable swim diaper but it’s important to also measure your child’s waist and thighs for the best fit.

Swim diapers look like regular swimming shorts and should fit snugly at the waist and thighs and be tight enough without leaving a red mark. Click on any Happy Nappy™ on the Splash About website and follow the ‘Check Size Before You Buy’ link for a size calculator to ensure the best fit.

5 Top Tips for using swim diapers

1. Disposable swim diapers aren’t very effective at keeping feces out of the pool, especially in the case of looser stools. If your child has had diarrhea, it’s best to skip swimming until they’ve fully recovered
   
2. No swim diaper can contain urine, so don’t put them on your child too soon! Urine in the pool is not a problem because the chlorine will kill any pathogens that may be present.
   
3. Regular diapers shouldn’t be used for swimming as they absorb large amounts of water, becoming very heavy — which can be unsafe for young children
   
4. Check your baby’s swim diaper regularly and change immediately if soiled.
   
5. Ensure toddlers have a potty break every 30 - 60 minutes. Most leaks into pools come from toddlers who can’t hold it or are so excited they forget to hold it

Happy Nappy™

Splash About is the leading brand in reusable swim diapers. The Happy Nappy™ Swim Diaper is made from neoprene. Its patented, unique shape is designed to fit baby's bottom and move as they do, preventing any gaping and stopping fecal leaks into the pool. The award-winning Happy Nappy™ is recommended by swim schools for swimming lessons worldwide, and for good reason! We have not had a reported leak in the Happy Nappy™ swim diaper for over 8 Years! Available in a wide range of colors and designs, the Happy Nappy™ really is a swimming lesson essential. 

How many swim diapers do I need?

Disposable swim diapers are designed to be used just once. If your child will be spending long periods out of the water (e.g. exploring the beach or having lunch at the swimming pool) then pack enough to ensure they have a clean, dry swim diaper every time they get back in the water. Wearing wet disposable swim diapers for extended periods out of the water can be uncomfortable for children and lead to diaper rash or chafing. If your child is suffering from diaper rash and you're worried about taking them swimming, find out how the Splash About Happy Nappy can help protect your little one's delicate skin here.

Reusable swim diapers work just like regular swimwear so shouldn’t cause soreness or chafing. As they do not hold in urine, they should be swapped for a regular diaper as soon as the baby gets out of the water. They are quick drying, so can be left to dry whilst out of the pool and reused when the baby returns to the water. At most, you should only require 2 reusable swim diapers to use on rotation so you always have a clean, dry swim diaper to hand in case of accidents.

Remember – disposable and reusable swim diapers are NOT designed to hold in urine so make sure you take your child for regular potty breaks or switch to a regular diaper when they’re not in the pool.

Swim Diaper FAQs

When should I stop using swim diapers?
Once your child is potty trained and you are confident they will tell you when they need a poo, you can stop using swim diapers. Splash About’s Happy Nappy™ range is suitable for children up to 3 years old and looks just like regular swimwear, so if your child has recently been potty trained, this range can give you peace of mind that there will be no leaks should an accident happen.

How do I clean and care for reusable swim diapers?
Reusable diapers should be hand washed in cool water. In the event of soiling, a reusable diaper can be machine washed on cold with non-biological detergent.Please note regular machine washing may compromise the integrity of the neoprene.

What are reusable swim diapers made from?
The Splash About Happy Nappy™ swim diaper range is made from super soft 1mm thick neoprene. This fabric is water resistant and will fit snugly to your baby's bottom, allowing them to move freely without any gaping. The neoprene used is a much thinner and softer neoprene than that used to make wetsuits.

How long will a swim diaper contain feces for?
Swim diapers are designed to hold feces long enough for you and your little one to leave the pool without any leakage. They are not designed to hold feces for a long period so you should ensure that you leave the pool immediately.

Will a swim diaper contain loose stool ?
Disposable swim diapers may not contain loose stools as they are not very robust and can leak around the seams. The Happy Nappy™ features wide cuffs made from specialist fabric which creates a tight (but comfortable) seal around the thighs and tummy, which will keep solid and semi-solid feces at bay. While very loose stools are completely normal for young babies that are exclusively breastfed, if your child is older and is experiencing diarrhea, then it’s important to keep them away from the water until they feel better.

Can my child wear a regular disposable diaper under a reusable swim diaper?
No, regular disposable diapers are designed to soak up liquid so can become bulky and uncomfortable very quickly if submerged in a swimming pool. However, disposable swim diapers can be worn under a reusable swim diaper.

Are swim diapers necessary?

Yes, swim diapers are necessary for babies and toddlers who are not yet potty-trained. Most public pools, water parks, and swim classes in the U.S. require them to help maintain hygiene and prevent contamination.

Swim diapers are designed to contain solid waste, reducing the risk of spreading germs that can cause illness. While they don’t hold in urine, they do help contain poop, which can prevent pool closures and health hazards if a child has a fecal accident in the water.

What should my child wear under a reusable swim diaper?
Most reusable swim diapers can be worn on their own, however, for extra protection you may want to combine with a disposable swim diaper, a Nappy Wrap, and/or liner. Some swimming pools and swim schools insist on a disposable swim diaper being worn under a reusable one, whilst others insist on the Happy Nappy Duo or Double Layer Diaper System, so check your local pool’s policy.

What Is the Difference Between a Regular Diaper and a Swim Diaper?

While regular diapers and swim diapers may look similar, they are designed for very different purposes:

1. Absorbency:
Regular diapers are made to absorb liquids like urine using absorbent gel materials.

Swim diapers are designed to not absorb water, so they won’t swell up when submerged. They only contain solid waste (like poop), not pee.

2. Function in Water
Regular diapers swell, sag, and become heavy in the pool, making them ineffective and uncomfortable.

Swim diapers stay lightweight and snug, allowing babies to move freely in the water without leaking solids.

3. Usage
Use regular diapers for everyday wear—naps, bedtime, and general use.

Use swim diapers when your child is in a pool, lake, or beach

Are swim diapers suitable for boys and girls?
Absolutely. The Splash About Happy Nappy™ comes in a range of designs suitable for boys and girls, or unisex designs suitable for both. 

You can view Splash About’s full range of Happy Nappy™ swimwear here.

Unsure about what to dress your baby in at the pool or beach? Read our guide Where to Start: Baby Swimwear Essentials

What about sizes for older children?
Most disposable and reusable swim diapers are suitable for children up to the age of three. There are a number of reasons why children older than this may require swim diapers

• Potty training is taking a little longer
• Your local pool requires all children under a certain age to use swim diapers
• Your child is affected by fecal incontinence

Available in 2-3 Years and 3-4 Years, these Toddler Jammers are designed to provide the same leak protection as the Happy Nappy™ swim diaper in a grown-up shorts design. Whilst they still have the specialist rib around the waist, the Jammers swap the thigh cuff for medical grade silicone around the inside of the leg, forming a seal that will not allow leaks, but that is discreet. The Toddler Splash Jammers are recommended by swim schools worldwide. 

Our well loved Happy Nappy™ and Happy Nappy Duo™ is now available in selected styles in sizes 3-4 years and 4-5 years. This gives another option to parents of toddlers who still need swim diaper support and who know and trust the Happy Nappy™ swim diaper and its benefits.

Available in kids sizes up 9 Years and adults from x-small size to x-large, they work in the same way as the Toddler Jammers with a snug fitting waist rib and silicone seal on the thighs to keep in all solid leaks. They look just like swimming shorts and can be worn on their own or worn with other swimwear over the top. There are styles suitable for boys and girls or unisex designs.