What we found on 10 swimsuit labels, and how to check your own in a minute.
At a glance
- Almost all swimwear produced around the world is made entirely from synthetic fabrics. Usually around 80% polyester or nylon, with 20% elastane for stretch. When we checked 10 swimsuits from well-known brands, all 10 were 100% plastic.
- Almost no swimwear built for swimming is completely plastic-free. The stretch nearly always comes from elastane, a synthetic fibre.
- Recycled nylon is considered the ‘eco’ option, but it is still plastic, sheds microplastics and may even contain higher levels of chemicals than virgin plastic yarns.
- Earthcove swimwear is a minimum of 98% organic cotton and 2% lycra, GOTS certified.
- To check any swimsuit, add up the natural fibres on the label (if there are any), check the lining separately and look for a certification you can verify.
Is there such thing as plastic-free swimwear? Almost no swimwear made for swimming is completely plastic-free. A swimsuit needs some stretch to stay put in the water, and that stretch nearly always comes from a synthetic fibre. Earthcove swimwear is 98% GOTS certified organic cotton and 2% lycra. We’re not proud of the lycra element, we sampled without it but it wouldn’t hold its shape and didn’t last past a couple of swims. And we’re an honest brand who don’t hide behind greenwashing, so we’ll always disclose what we use.
But does swimwear need to be made from 100% plastic? Also no. In my opinion it’s totally unnecessary to make swimwear from entirely synthetic fabrics, and I also believe this is hugely harmful to human health and our environment too. Synthetic fabrics are treated with harsh chemicals, known to harm our health, and they shed microplastics every time they’re worn or washed.
So why did I set out to create plastic-free swimwear? This all started by mistake. In the summer of 2023, my kids were coming home from school and changing into their swimwear to run around in the garden and play with the hose. Their swimwear became their go-to summer clothing, and it dawned on me that it was entirely plastic. I’d been running a plastic-free children’s brand, Pure Earth Collection, for six years, and was extremely careful about keeping my kids away from unnecessary synthetic fabrics. I searched the internet for natural swimwear options, but checking the materials I was only finding polyester, nylon, elastane. All of the swimwear I could find was made from plastic, and I couldn’t find any alternatives.
That question (why is all swimwear plastic?) is what eventually became Earthcove.
So I set about designing and sampling plastic-free swimwear. We got really close, with our 98% organic and 2% lycra blend (to be clear, we’re not claiming this is plastic-free, but there’s 98% less plastic than most swimwear and, given its GOTS certification, it’s one of the cleanest and least toxic options on the market globally). So always check your labels, read what the materials are, think about what that means, and check for important certifications which ensure the materials are free from harmful chemicals.
What is most swimwear made from?
Most swimwear is made from synthetic fibres, which are plastics spun into thread. Here is a quick decoder for the names you will see on a label.
A table showing with swimwear is made of.
Elastane is called spandex in the US, and Lycra is a brand name for it. All three are a synthetic fibre made mostly from polyurethane [5].
More and more swimwear now uses recycled nylon or recycled polyester, often made from plastic bottles or old fishing nets. Until now, it’s been regarded as the ‘eco’ option, but recycled plastics have been shown to have more chemicals than virgin plastic, so there are concerns around the safety of recycled yarns for use in clothing. More on that below.
None of this is unusual. Synthetic fibres now dominate the whole clothing world. 69% of all fibre made worldwide in 2024 was synthetic, and polyester alone was 59%, according to Textile Exchange [1]. Swimwear sits right at the heart of that.
Figure 1. In 2024, 69% of all fibre made worldwide was synthetic. Polyester was 59%, other synthetics 10%, cotton 19% and everything else 12% [1].
What did we find when we checked 10 labels?
We wanted real numbers, not guesses. So in November 2026 we asked Google Search to list popular UK swimwear brands, and took the first 10 it gave us. For each brand, we checked the first swimsuit or pair of swim shorts we could find with its fabric composition listed online. We didn’t pick them to prove a point. We just read what was there, and we encourage you to do the same experiment to see what you find.
All 10 were 100% plastic. Not one contained a single natural fibre.
Seven were nylon (polyamide) with elastane for stretch. One was a sports costume made from polyester and PBT, a stretchy type of polyester. The other two, both men’s swim shorts, were 100% recycled polyester. Nylon or polyester made up between 78% and 100% of each fabric.
Four of the 10 used recycled fibres, which is often how swimwear gets sold as the ‘eco’ choice. All four were still 100% plastic.
Only two product pages said what the lining was made from, and both linings were synthetic too. The other eight didn’t say. That is one more reason to turn a swimsuit inside out before you buy.
Figure 2. All 10 swimsuits we checked were 100% plastic. Nylon or polyester made up 78% to 100% of each fabric, with elastane making up the rest. Earthcove is shown for comparison at 98% organic cotton and 2% lycra [7].
We have not named any shops or brands. This is not about pointing fingers. It is about showing what normal looks like, so you know what you are reading next time you shop, in a changing room or online.
Is recycled nylon plastic-free?
No. Recycled nylon is still plastic. Textile Exchange counts recycled polyamide as a synthetic fibre, right alongside the new version [1].
So if a label says “80% recycled nylon, 20% elastane”, that swimsuit is 100% plastic. And recent research has shown this could be more toxic, not less. It is not a plastic-free one.
Figure 3. A typical swimsuit and a recycled nylon swimsuit both add up to 100% plastic. Earthcove is 98% organic cotton and 2% lycra. Both labels are real, from our November 2026 check.
It is worth knowing, because “recycled” and “plastic-free” can blur together in marketing. They are not the same thing.
Why isn’t Earthcove 100% cotton?
Because a swimsuit has to work in the water, and cotton on its own has very little stretch. A 100% cotton costume can sag, gape and slide off little shoulders once it is wet. That is not much fun for anyone.
So we sampled and tested our first costumes over a full summer and settled on the smallest amount of stretch that keeps a suit in shape: 2% lycra. The other 98% is GOTS certified organic cotton.
Cotton does behave differently to nylon, but it’s a trade off of functionality versus chemical load. It holds more water and dries more slowly. In our own wear testing, though, it lasted at least twice as long before sagging or bobbling. Our fabric was also tested by Intertek for sun protection and rated UPF 50+ under EN 13758‑1 [6].
We could round 2% down and call ourselves plastic-free. We never will because that’s misleading and we want our customers to know what we’re about. 2% is small, but it is real, and you deserve to know exactly what your family is wearing. We’re working on developing a bio-lycra at the moment, and really hope that this becomes a viable option soon.
Is any swimwear 100% plastic-free?
Yes, but it is usually beachwear rather than swimwear. Some crochet pieces, cover ups, beach dresses and kaftans are made only from cotton or linen. They are lovely for lounging on the sand.
In the water, without stretch, most of them get heavy and lose their shape fast. If you see a stretchy swimsuit described as plastic-free, have a look at the label. Stretch has to come from somewhere, and in swimwear it almost always comes from elastane.
How do I read a swimsuit label?
You do not need a chemistry degree. Turn the swimsuit inside out and work through these five steps.
Figure 4. The Earthcove five step label check. Save it to your phone for your next shopping trip.
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Find the composition label. It is usually sewn into a side seam. In the UK, clothing must list every fibre by name and percentage, from largest to smallest [3].
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Add up the natural fibres. Cotton, organic cotton, linen and hemp are natural. Nylon, polyamide, polyester, elastane and spandex are synthetic. Take the natural total away from 100 and that is your plastic share.
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Count recycled fibres as plastic. Recycled nylon or recycled polyester still adds to the plastic share.
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Check the lining separately. Many swimsuits have a lining with its own composition, often listed under “Lining” on the same label. A cotton outer can still have a nylon lining. In the US, linings do not always have to be listed, so if it is missing, ask [4].
- Look for a certification you can verify. A logo on its own is not proof. GOTS labels carry a licence number you can look up in the GOTS public database. To carry the GOTS “organic” label, a product must contain at least 95% certified organic fibres [2].
Figure 5. GOTS label grades. "Made with organic" needs at least 70% certified organic fibre and "organic" needs at least 95%. Earthcove is 98% [2].
Every small change adds up
It’s not about fear, it’s about awareness. Most of us have never been shown how to read a swimsuit label, and the industry has not made it easy.
You don’t need to overhaul your entire life overnight. Next time you buy swimwear, turn it inside out and read the label. That one habit will tell you more than any marketing ever could.
If you would like to see what 98% organic cotton looks like in the water, our Swimwear for all collection has styles for kids, women and men.
Every small change adds up.
Emma x
Quick answers
Is there such a thing as plastic-free swimwear?
Almost none that is built for swimming. When we checked 10 swimsuits from well-known brands sold in the UK, all 10 were 100% plastic. Swimsuits need stretch, and that stretch nearly always comes from elastane, a synthetic fibre. Fully plastic-free pieces tend to be beachwear for lounging rather than swimming.
Is 100% cotton swimwear good for swimming?
Cotton without any stretch tends to sag and lose its shape in water. A small amount of elastane, around 2%, helps a cotton swimsuit hold its shape while keeping it mostly natural.
Is elastane plastic?
Yes. Elastane, spandex and Lycra are names for the same type of stretch fibre, which is made mostly from polyurethane, a plastic.
Is recycled nylon swimwear plastic-free?
No. Recycled nylon is still nylon, a synthetic fibre. The swimsuit is still made from plastic.
What is Earthcove swimwear made from?
Earthcove costumes are 98% GOTS certified organic cotton and 2% lycra, with fabric tested by Intertek and rated UPF 50+.
Sources
- Textile Exchange, Materials Market Report 2025 (September 2025). Global fibre production figures for 2024, including synthetic and recycled polyamide.
- Global Organic Textile Standard, Label grades. The 95% minimum for “organic” labelling.
- UK legislation, Regulation (EU) No 1007/2011 as retained in UK law, Article 9 (fibre names and percentages in descending order) and Article 11 (main linings).
- US Federal Trade Commission, Threading Your Way Through the Labeling Requirements Under the Textile and Wool Acts (linings and fibre disclosure).
- US Federal Trade Commission, 16 CFR 303.7, generic fibre names including spandex.
- Intertek, UPF test report TRPT24024771 (March 2024), tested to EN 13758‑1:2001+A1:2006.
- Earthcove label check, November 2026. The first 10 brands returned by a Google Search for popular UK swimwear brands, one product each, using the fabric composition on the product page.
