If you order ice on an airplane, there's a chance it could be riddled with bacteria. Ice is typically made from the plane's supply of tap water, which is kept in tanks that have been found to breed bacteria. Even flight attendants refuse to drink anything made with an aircraft's tap water.

While the idea that airplane water is "riddled" with bacteria is a common travel trope, the reality in 2026 is a bit more nuanced. The water used for the sinks in the lavatories and for the coffee/tea served on board comes from large storage tanks that are filled at various airports worldwide. Studies, including a famous 2019 report by the Hunter College NYC Food Policy Center, have shown that these tanks are not always cleaned as frequently as they should be, and "coliform" bacteria (which can indicate the presence of other pathogens) are occasionally found. However, the EPA's Aircraft Drinking Water Rule (ADWR) requires airlines to test their water samples and disinfect the tanks regularly. Most health experts suggest that while the water is generally safe for washing hands, it is best to avoid drinking "tap" water on a plane. The coffee and tea are usually safe because the water is heated to a temperature that kills most bacteria, but it may not always reach a rolling boil. For the safest experience, travelers are always advised to stick to sealed bottled water or canned beverages provided by the flight attendants.