ASOS is one of the world's largest online fashion retailers, stocking over 850 brands plus their own label. That's thousands of products — and the vast majority of them are made from synthetic fabrics. When you can't touch the fabric before buying, knowing the composition matters more than anywhere else.
Here's what ASOS clothing is actually made of, why the online-only model makes fabric awareness even more important, and how to find the natural fibre pieces hiding in the noise.
The ASOS Fabric Problem
ASOS has a unique challenge — and a unique excuse. Because they stock hundreds of third-party brands alongside their own ASOS Design, ASOS Luxe, and Collusion lines, the fabric composition varies wildly from product to product.
But the overall trend is clear: synthetic fabrics dominate.
- ASOS Design — their own-brand range is heavily polyester-based, particularly in dresses, blouses, and going-out wear. Cheaper pieces are almost always majority synthetic.
- Collusion — their Gen-Z focused line uses a lot of recycled polyester. Still polyester. Still sheds microplastics. Still doesn't breathe.
- Third-party brands — varies from 100% polyester fast fashion (Boohoo, PrettyLittleThing, Missguided) to genuine quality (natural fibre brands like Arket, COS, and selected premium labels).
- ASOS Luxe — their premium line uses better fabrics but isn't immune to synthetic blends.
The problem is that on ASOS, a polyester dress and a linen dress sit side by side on the same page, at similar prices, with similar styling. The photos look identical. The only way to tell them apart is the fabric composition — and ASOS buries that in the product details.
Common ASOS Fabrics
| Fabric | Where You'll Find It | Verdict |
|---|---|---|
| Polyester | Dresses, blouses, going-out wear, activewear, most ASOS Design pieces | Plastic. Doesn't breathe, traps heat, breeds bacteria, sheds microplastics. |
| Cotton | T-shirts, basics, denim, some ASOS Design pieces | Good. Breathable, comfortable, biodegradable. Look for 100% cotton. |
| Viscose | Summer dresses, flowy tops, midi skirts | Decent. Semi-synthetic, no microplastics, but chemically processed. |
| Nylon/Polyamide | Tights, swimwear, underwear, activewear | Synthetic. Slightly better than polyester against skin but still plastic. |
| Elastane | Blended into almost everything for stretch (2-5%) | Fine in small amounts. Synthetic but functionally necessary for stretch. |
| Linen | Summer collections, premium pieces | Excellent. Natural, breathable, biodegradable. Worth seeking out. |
| Acrylic | Knitwear, sweaters, scarves | The worst. Sheds 730K microplastic particles per wash. Avoid. |
Why ASOS Is Harder Than Other Retailers
Shopping for fabric on ASOS is harder than on Zara or H&M for one simple reason: ASOS is a marketplace.
On Zara, you're dealing with one brand's fabric choices. You can learn their patterns — their basics are usually cotton, their dresses are usually polyester, their premium pieces might use linen. On ASOS, you're dealing with hundreds of brands with completely different fabric strategies.
A "midi dress" search on ASOS might return:
- A 100% silk dress from a premium brand — $180
- A 100% polyester dress from ASOS Design — $45
- A 95% cotton dress from Monki — $55
- A 70% polyester / 30% viscose blend from New Look — $35
They all look similar in photos. The price gives some clues, but not always — some expensive ASOS items are still polyester, and some affordable ones are cotton. The only reliable way to tell is checking the fabric composition. For every. Single. Item.
Nobody does that manually across 50 search results. That's exactly why Fibr exists.
Fibr reads the fabric composition of every product on supported retailers and shows it as a colour-coded badge right on the image. Green for natural, yellow for mixed, red for synthetic. You see the composition before you click — across every brand, every product, every page.
ASOS's Sustainability Claims
ASOS has a "Responsible Edit" — a curated selection of products that meet certain sustainability criteria. They also have targets around recycled materials, carbon reduction, and circular fashion.
Here's the reality check:
- Recycled polyester is still polyester. It still sheds microplastics, still doesn't breathe, still takes 200+ years to decompose. ASOS's Collusion line leans heavily on this.
- "Responsible Edit" is a tiny fraction. The vast majority of ASOS products aren't in this edit. Scrolling past a "Responsible" badge doesn't make the other 95% of products sustainable.
- Third-party brands set their own rules. ASOS has limited control over the fabric choices of the hundreds of brands they stock. A sustainability policy for ASOS Design doesn't apply to Boohoo or PrettyLittleThing products sold on the same platform.
The most reliable approach: ignore the marketing, check the label. Product by product. Fabric by fabric.
How to Find Natural Fibres on ASOS
Natural fibre clothing exists on ASOS — you just have to know where to look:
- Filter by material. ASOS has a "Material" filter in search. Use it to select cotton, linen, silk, or wool. It's not perfect (blends still show up), but it narrows the field.
- Check the brand. Some ASOS brands consistently use better fabrics: Arket, COS, & Other Stories, Weekday, and selected premium labels. ASOS Design basics (t-shirts, joggers) are often cotton.
- Read the product description. Scroll to "About Me" or "Product Details" — that's where ASOS lists composition. If it starts with "polyester", move on.
- Use Fibr. See the composition on every product image without clicking into anything. Filter out synthetic-heavy items at a glance.
Frequently Asked Questions
Does ASOS use polyester?
Yes. Polyester is the most common fabric across ASOS's own-brand lines (ASOS Design, Collusion) and many of the third-party brands they stock. It's particularly dominant in dresses, blouses, and going-out wear. ASOS also uses "recycled polyester" in their Collusion line — which is still polyester, still synthetic, and still sheds microplastics.
Is ASOS sustainable?
ASOS has sustainability targets and a curated "Responsible Edit," but the majority of products on the platform don't meet these criteria. As a marketplace stocking hundreds of brands — including ultra-fast fashion labels like Boohoo and PrettyLittleThing — ASOS's overall fabric profile is heavily synthetic. Sustainability on ASOS is a product-by-product question, not a brand-level one.
Is ASOS fabric quality good?
It varies enormously because ASOS stocks hundreds of brands. A linen dress from Arket and a polyester dress from ASOS Design are completely different products in terms of fabric quality, even though they appear on the same site. The single best predictor of quality is fabric composition — cotton, linen, silk, and wool garments will generally feel and wear better than polyester equivalents, regardless of brand or price point.