A child's first race suit is a big step up from a training costume, and it is usually bought against a deadline: a first gala, a county qualifier, or a birthday. This guide covers what a race suit is, when a junior swimmer genuinely benefits from one, how the main styles differ, and how to size it so it fits first time and does not have to be sent back. Getting the size right is the single most important decision here, and it is where most first-time buyers go wrong.

What is a race suit, and how is it different from a training suit?

A race suit is a close-fitting swimsuit built to a World Aquatics (WA) approved specification for competition. It holds the body firm, streamlines the swimmer and reduces resistance in the water, which is why swimmers wear one for racing rather than for everyday training.

Not every race suit is a high-end tech suit. The top-of-the-range tech suits, made from bonded, water-repellent fabric with very high compression, are aimed at experienced swimmers. A child's first race suit is usually an entry-level model: typically stitched rather than bonded, with lighter compression, so it is easier to get on and more comfortable for a newcomer.

The difference a parent notices first is how it goes on. A race suit is meant to feel tight and takes real effort to put on correctly, which is completely normal and part of how it works. It is also an investment piece, so it is worn for races and important sets, not for five training sessions a week. For junior club events, look for suits carrying the WA approval, since many age-group competitions require it.

Does your child need a race suit yet?

Not every young swimmer needs a race suit, and buying one too early is a common mistake. The honest test is whether your child is racing, not just training. A swimmer who has moved into a competitive squad and is entering galas, open meets or county qualifiers will feel the benefit. A swimmer still finding their feet in lessons will not, and the money is better spent on good goggles and training kit.

Much of the advice parents find online is American, and the rules quoted with it often are too. USA Swimming, for example, restricts race suits for swimmers aged 12 and under. That is a US rule, and the UK nations set their own. In Scotland, Scottish Swimming does not allow swimmers aged 13 and under to wear technical swimsuits at age-group competitions it licenses or registers, although traditional styles such as kneeskins and jammers are still allowed. Parents should check their own club's and their national governing body's current guidance before assuming it applies here. If you are unsure whether your child's events call for a WA approved suit, our swimwear experts can talk it through with you.

Kneeskin or jammer: which style does your child need?

Junior race suits come in two main shapes. Girls generally wear a kneeskin, which covers the torso and extends down to just above the knee. Boys wear a jammer, a close-fitting short that runs from the waist to just above the knee. Both are WA approved race styles; the choice is set by the swimmer, not by preference.

Within each style, models differ in how aggressive the compression is and how the suit and its fabric are built. Entry-level junior suits are more forgiving and easier to get on, which suits a first-time racer. The more advanced suits give stronger compression and a more precise fit, which an experienced age-grouper will appreciate but a newcomer may find a struggle. Our swimwear experts match the model to the swimmer's age, build and events rather than selling the most expensive option in the cabinet.

How do you size a child's race suit correctly?

Sizing is where most first race suits go wrong, and it is worth slowing down for. Order from the brand's own measurements, not your child's age or height. Each brand sizes differently, so a measurement, taken with a tape around the chest, waist and hips, is the only reliable guide. For a boy's jammer in particular, height does not come into it; the waist and hip measurements decide the size.

A race suit should feel considerably tighter than a training costume, and it should take a few minutes of patience and care pulling to get on. That tightness is the compression doing its job. The trap is going too small on purpose. One piece of UK club advice we frequently hear tells parents to order two sizes down from a training suit, and we see the result: far more first race suits come back because they were too small than because they were too big. Order the size the chart gives you for the measurements, and allow time to ease it on properly before race day.

How do you get a race suit on properly?

A race suit takes time to put on, and rushing it is how seams and nails do damage. Allow a good ten to fifteen minutes the first time, with dry hands and dry skin, and work it up the body a few centimetres at a time rather than yanking it.

Expect it to feel unfamiliar, and a little uncomfortable, the first time. We see this every day when fitting swimmers in store: a child used to a training costume often finds a race suit tight and strange at first. Let them wear it around the house before race day so it feels normal by the time they step onto the block.

Three things to check before race day

How do you care for a race suit, and what if it tears?

A race suit lasts longest when it is treated as race kit. Rinse it in cold water after every wear, never wring it, and dry it flat away from direct heat and radiators. Keep it out of the hot tub and the shower if possible, as warm water and chemicals break down the fabric faster than the pool does. A little loss of compression over a season of racing is normal wear, not a fault.

Never put a race suit in a washing machine or tumble dryer, as the spin, heat and detergent are hard on the fabric and seams. Wash it by hand in cool water instead. A dedicated race suit wash, such as Rinse Race Suit Wash, is a gentle way to neutralise chlorine and remove odour, then rinse thoroughly and dry flat away from direct heat.

Seams do sometimes give way, and a peeling WA approval label worries parents before a race. This is where being one of the only UK retailers with a race suit repair service matters: in many cases a race suit can be repaired rather than replaced. Repairs take time, so if a big competition is coming up, send it to us as early as you can rather than the week before. If you are unsure whether a mark or a lifting seam is normal or a genuine fault, send us a photo and our swimwear experts will tell you honestly.

If your child competes under World Aquatics rules, it is worth knowing which suits qualify. World Aquatics publishes its own approved swimwear information, and we only stock race suits that meet it.

Written by a swimwear specialist at Allens Swimwear, 50 years of expert fitting.