Travellers carrying stainless steel or other metal water bottles are being reminded that these must be empty before passing through airport security, even at UK airports where the 100ml liquid rule has been scrapped. The new generation of CT scanners cannot penetrate the double-layer insulation of metal bottles, making it necessary for passengers to empty them to ensure safety.
As of May 2026, the two-litre liquid rule is in place at London Heathrow (all terminals), London Gatwick, Birmingham, Edinburgh, Bristol, Belfast International, and Belfast City. At most airports, there is no limit on the number of bottles you can carry, but the exception applies to metal containers.
Edinburgh Airport has confirmed that passengers must empty any liquids from metal bottles before security. Its website states: 'If you are carrying metallic or double-walled containers (including vacuum flasks, thermos flasks and metallic water bottles), please ensure the container is empty prior to the security checkpoint. You can then top up your bottles for free after security.'
Plastic water bottles of any size should generally pass through scanners without issue, though some airports like Gatwick may ask passengers to remove drinks from these as well. Gatwick's website says: 'You can take any empty drink containers (plastic or metal) of any size through security.'
Dedicated liquids disposal sinks and bins are available in front of security screening lanes, and most terminals offer free water bottle refilling stations after security. Passengers are advised to check their specific airport's website for the latest rules.
