Do Thermos insulated drink tumblers have PFAS?
Thermos insulated drink tumblers average 76 out of 100 on PFAS Authority's PFAS and toxin screen across the 7 Thermos insulated drink tumblers graded as of October 2026, above the 70 out of 100 median for the 25 other insulated drink tumblers brands graded alongside it.
Thermos insulated drink tumblers average Excellent on our four-band scale. 7 of the 7 we graded are worth buying. That is above 84% of the insulated drink tumblers 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.
Thermos insulated drink tumblers worth buying Good or better, best-graded first
Thermos
Stainless King Tumbler
- Stainless steel interior, plastic exterior lid
- We found no PFAS statement from the brand
- Plastic lid degradation and leaching, The plastic lid and silicone gasket can degrade over years of repeated…
Thermos
Stainless King Travel Tumbler
- Stainless steel exterior, vacuum-insulated, minimal internal coating
- We found no PFAS statement from the brand
- Silicone lid and gasket degradation, Silicone seals can accumulate mold, mildew, or bacterial biofilm if not…
2 hazards checked on this product. See all of them.
Thermos
Stainless Steel Tumbler w/ Slide Lock Lid
- Stainless steel tumbler with plastic slide lock lid
- We found no PFAS statement from the brand
- Plastic lid degradation, Polypropylene or acetal lids can develop micro-cracks and surface crazing over 2-4…
2 hazards checked on this product. See all of them.
Thermos
Stainless Steel Tumbler Slide Lock Lid
- Stainless steel body, plastic/silicone lid
- We found no PFAS statement from the brand
- BPA & bisphenols, Thermos does not publicly confirm the lid polymer type or state whether it contains BPA…
2 hazards checked on this product. See all of them.
Thermos
24oz Insulated Cold Tumbler
- Stainless steel and double-wall insulation
- We found no PFAS statement from the brand
- Seal/gasket degradation, Double-wall tumblers often use silicone or rubber gaskets; prolonged use and thermal…
2 hazards checked on this product. See all of them.
Thermos
24oz Double WALL Tumbler
- Stainless steel interior, plastic/polymer exterior
- We found no PFAS statement from the brand
- Polymer exterior durability and degradation, Repeated thermal cycling and dishwasher exposure can cause…
2 hazards checked on this product. See all of them.
Thermos
Guardian Stainless Steel Tumbler
- Stainless steel interior and exterior
- We found no PFAS statement from the brand
- Stainless steel corrosion and pitting, While rare, aggressive acids or prolonged salt water contact can…
2 hazards checked on this product. See all of them.
Better insulated drink tumblers from other brands
Graded higher than the Thermos average of 76.
Klean Kanteen
20oz TKWide with Café Cap, Tofu
- Stainless steel bottle, stainless steel cap
- The brand calls it PFAS-free, which we have not verified
- Powder-coat cap degradation over time
3 hazards checked on this product. See all of them.
Klean Kanteen
16oz Rise Tumbler
- Stainless steel body, powder-coat finish
- The brand calls it PFAS-free, which we have not verified
- Powder-coat finish degradation
3 hazards checked on this product. See all of them.
Klean Kanteen
Insulated TKWide Cap
- Stainless steel bottle, plastic cap and silicone gasket
- The brand calls it PFAS-free, which we have not verified
- Silicone gasket degradation and leaching
3 hazards checked on this product. See all of them.
The same question, asked of the other insulated drink tumblers brands
Best average grade first. Thermos averages 76.
See every Thermos product we grade on the Thermos brand page, or the full insulated drink tumblers ranking.