Carry On Bags:
No
Checked Bags:
Yes (Special Instructions)
The FAA allows one small Medical-Clinical Thermometer (Mercury) per passenger for personal use in checked bag only.
The thermometer must be in a protective case.
Tip: Thermometers with a red line instead of silver are not mercury and not restricted. Digital thermometers are also not restricted, unless powered by lithium batteries. See FAA regulations for more information on quantity limits.