Rules differ by region: Mercury thermometers are banned from both carry-on and checked baggage worldwide — mercury is classified as a dangerous good under IATA regulations. Digital thermometers are unrestricted in all regions.
💼 Cabin bag
Depends
Digital or non-mercury thermometers: permitted. Mercury thermometers: prohibited — mercury is a IATA-classified dangerous good.
✈️ Hold (checked)
Depends
Digital or non-mercury thermometers: permitted. Mercury thermometers: prohibited in checked baggage by IATA dangerous goods regulations.
💡 Tip: Digital and non-mercury thermometers have no restrictions. Mercury thermometers are the problem — mercury is a hazardous material banned from aircraft by IATA. Replace with a digital model before flying.
Airline-specific rules
🌍All airlinesMercury thermometers are prohibited on all commercial flights due to the toxicity and spill risk of mercury.
Related items
Browse all Medical →Based on official TSA guidelines. Rules vary by airline and route — always verify with your carrier before travel. · Rules last verified May 2026.
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