A “plastic-free kettle” claim should describe the hot-water path, not the color of the shell.
What we actually check
- Chamber / inner vessel material
- Water windows and tubes
- Named seals (often silicone)
- Any plastic parts that stay in contact with hot water during normal boil
A stainless exterior with plastic water windows in the brew path typically Fails. An all-metal path with disclosed silicone seals can Pass or land Partial depending on the rest of the path. See scored models in the kettles guide and the Cosori vs Fellow vs Breville comparison.
Why this matters for searchers
Retail titles often lead with “stainless steel kettle” while the materials sheet still lists polypropylene windows or unspecified plastics. We keep mainstream brands on the page — including fails — so the shelf matches what you actually see in stores.
We do not run lab leachate tests. Verdicts link manufacturer or retailer materials sources on each product card.
FAQ
Is a stainless exterior enough?
No. We score what hot water touches: chamber, windows, tubes, and named seals. Plastic water windows in the brew path typically Fail even when the outer shell looks metal.
Are silicone seals automatic fails?
Named silicone seals can still land at Pass or Partial when the primary water path is metal/glass and the maker discloses the seal. Undisclosed plastic in the water path does not.
Affiliate note: product guides may include Amazon links tagged nocoatingkitc-20. See disclosure.