Does COS swimwear have PFAS?
COS swimwear averages 59 out of 100 on PFAS Authority's PFAS and toxin screen across the 8 COS swimwear products graded as of October 2026, above the 54 out of 100 median for the 27 other swimwear brands graded alongside it.
COS swimwear averages Good on our four-band scale. None of them clear our buy threshold. That is above 87% of the swimwear brands we grade.
PFAS Authority is a scoring system, not a laboratory. We do not test products ourselves. Grades are model-based, built from published ingredients, materials, certifications, brand disclosures and third-party lab results where they exist. See the rubric.
Graded and flagged Poor and Bad, we’d swap these
COS
Bonded-Scuba V-Neck Swimsuit
- Nylon/polyamide blend (bonded construction)
- We found no PFAS statement from the brand
- Azo dyes and colorant residues, Swimwear dyes may include azo compounds (linked to skin sensitivity in rare…
4 hazards checked on this product. See all of them.
COS
Women's Asymmetric Double-Faced Swimsuit
- Polyamide (nylon) blend; double-faced woven textile
- We found no PFAS statement from the brand
- Azo dyes and colorant chemistry, Polyamide swimwear is typically dyed with reactive or disperse dyes, some of…
3 hazards checked on this product. See all of them.
COS
Women's Bonded-Scuba V-Neck Bikini Top
- Nylon/polyamide blend (bonded-scuba knit)
- We found no PFAS statement from the brand
- Azo dyes, COS nylon swimwear may use azo dye colorants; while bluesign-certified facilities restrict…
4 hazards checked on this product. See all of them.
COS
Women's Bonded-Scuba V-Neck Swimsuit in Red
- Bonded scuba neoprene/polyester blend
- We found no PFAS statement from the brand
- Azo dyes in polyester backing, Red polyester swimsuit backing may contain azo dyes; while restricted in EU…
3 hazards checked on this product. See all of them.
COS
Women's Bonded Swimsuit in Brown
- Nylon/polyester blend with elastane (bonded swimwear construction)
- We found no PFAS statement from the brand
- Adhesive/bonding layer leachates, Bonded swimwear adhesives may contain residual solvents or plasticizers; no…
3 hazards checked on this product. See all of them.
COS
Women's Contrast-Trim Swimsuit
- nylon/elastane blend swimsuit fabric
- We found no PFAS statement from the brand
- Microplastic shedding during use and laundering, Elastane-blended swimwear sheds microfibers, particularly…
COS
Scuba Swimsuit
- polyamide (nylon) or polyester blend
- We found no PFAS statement from the brand
- Azo dyes in synthetic textiles, Polyamide and polyester both commonly accept azo-based reactive dyes during…
3 hazards checked on this product. See all of them.
COS
Women's Bonded-Scuba V-Neck Swimsuit
- Polyester scuba-knit bonded fabric with likely water-repellent coating finishing
- We found no PFAS statement from the brand
- PFAS, Standard for bonded scuba-knit swimwear unless explicitly marketed otherwise. COS has not disclosed…
5 hazards checked on this product. See all of them.
Better swimwear from other brands
Graded higher than the COS average of 59.
Patagonia
Women's Bottom Turn Racerback Bikini Top
- Nylon/polyester blend with elastane (standard swimwear)
- The brand calls it PFAS-free, which we have not verified
- Elastane (spandex) degradation under heat or chlorine
Solid & Striped
Taylor One Piece Seersucker Plaid
- Cotton/cotton-blend seersucker plaid
- We found no PFAS statement from the brand
- Azo dyes and colorfast stability
2 hazards checked on this product. See all of them.
Adidas
Women's Mexicana Florals Tie-Back Swimsuit
- Polyester/nylon swimsuit fabric, likely uncoated or standard finish
- Azo dyes and synthetic colorants
4 hazards checked on this product. See all of them.
The same question, asked of the other swimwear brands
Best average grade first. COS averages 59.
See every COS product we grade on the COS brand page, or the full swimwear ranking.