Every security tray in Britain is a small museum of 2006. That was the year a foiled plot turned a temporary emergency measure — no liquid container over 100ml, everything in a clear plastic bag — into two decades of airport ritual. The rule was never meant to be permanent. It survived because the machines that could replace it did not exist yet.
Now they do. And the strangest chapter of the story is the current one: the rule is not ending everywhere at once. It is ending airport by airport, on each operator’s own schedule, which means the allowance that waves you through on the way out may not exist at the airport you fly home from.
What a CT scanner actually changes
The new lanes are built around computed-tomography scanners — the same imaging principle as a hospital CT. Instead of a flat X-ray silhouette, the machine builds a rotatable 3D model of your bag and analyses what the materials are, not just what shape they make. That is why the two changes always arrive together: liquids and large electronics can stay in the bag, because the scanner no longer needs them separated; and the 100ml ceiling can rise, because the machine can tell shampoo from something worse.
The map, in the airports’ own words
Bristol is the clearest case of the new regime. Its security page states: “The current maximum size of each liquid container at Bristol Airport is 2 litres. Keep your liquids in your bag (there’s no need to use a clear plastic bag).” One caveat survives from the old world — metal drink bottles still go through empty.
Edinburgh got there first in Scotland, after a £24 million rebuild of its search hall with eight new lanes. Birmingham crossed over in 2025. And Heathrow shows the rule bending even where it has not formally fallen: its connections guidance already lets transferring passengers keep liquids up to two litres in their cabin bags while clearing the transfer checkpoint.
Then there is the halfway house. Stansted and Luton both run CT scanners — nothing comes out of your bag any more, and the clear plastic bag is history — but both still cap every container at 100ml. Faster trays, same old limit. Stansted is blunt about the consequence: anything over 100ml does not fly, even if the bottle is half empty.
The verified state, August 2026
The return flight is where people get burned
Fly Bristol to Alicante with a 500ml bottle of sun cream and security will not blink. Fly home a fortnight later and that same bottle is confiscated at a Spanish checkpoint that never left 2006. The asymmetry is not a loophole or an oversight — Bristol’s own page tells passengers to check the hand-baggage rules of the airport they return from. The airports know the map is split. Most travellers do not.
Why this article will change
The split map above is a snapshot, verified against each airport’s official security pages on 4 August 2026 and stored with its sources in our files. Airports flip on their own schedule — when one does, our security notes at /brs, /edi, /stn and /ltn update on re-verification, and this article updates with them. If your airport is not listed here, we have not verified it yet — check its own security page the week you fly.