Heathrow’s cabin liquid limit is two litres per container at every terminal — T2, T3, T4 and T5 — under rules verified as of October 16, 2026. Clear plastic bags are no longer required, and laptops and large electronics can stay in your bag.
The 100ml rule has not vanished from your journey, though. Heathrow tells connecting passengers to check the rules at their onward airport or the point they fly home from, because plenty of airports still cap containers at 100ml.
If you came looking for a terminal-by-terminal breakdown of Heathrow’s liquid rules, the honest answer is that there isn’t one to give. Terminals 2, 3, 4 and 5 all run the same allowance. What genuinely differs between them is the queue, the walk to the gate and how long security takes on a Monday morning — operational detail, not regulation.
The rule that can still catch you out sits somewhere else entirely: your connecting airport. Pack a two-litre bottle of sunscreen for a Heathrow departure and it sails through. Carry the same bottle through a transfer hub that never loosened its limits and it will not.
Heathrow’s own guidance says as much, telling transfer passengers to check the security rules at their onward airport or the point they return from. That single line is the most useful sentence in the whole policy, and it is the one most travelers skim past.
Because this rule has moved before — and moved back — everything below is dated. Rules verified as of October 16, 2026.
Heathrow’s liquid rules, verified as of October 16, 2026
Every operating terminal at Heathrow now allows cabin liquids in containers holding as much as two litres. The figure applies to each container. One large bottle now does the job that a cluster of small ones used to.
Two other changes travel with it. Heathrow no longer requires liquids to go into a clear plastic bag, and laptops and large electronics can stay inside your cabin bag while it is screened.
There is one catch general coverage tends to skip. Refillable bottles built from metal, or double-walled and vacuum-insulated designs, need to be empty before they pass through the scanner.
Their construction blocks what the machine can image, so a full insulated flask reads as an obstruction rather than a container of liquid. Empty it at the lane and you keep it. Leave it full and you are repacking in front of a queue.
What changed, and when
The two-litre allowance rests on equipment, not on a change of heart. Terminals 2, 3, 4 and 5 have moved to next-generation computed tomography scanners, which is what lets the limit sit at two litres across the board rather than in patches.
The rule has not been stable, though. In June 2024 the Department for Transport sent six airports — London City, Teesside, Newcastle, Aberdeen, Leeds Bradford and Southend — back to the 100ml limit, after concerns that scanners were misreading some larger items. Those airports had already loosened their limits or were preparing to.
What followed is the part nobody has explained cleanly. Some UK airports kept or restored the two-litre allowance; others stayed at 100ml.
Government guidance still tells travelers to check each airport rather than assume the country works one way, and it does not name every airport in the split. Secondary reporting puts Bournemouth, Belfast City, Belfast International, Bristol, Edinburgh, Birmingham, Gatwick and Heathrow on the two-litre side, with Southend, Leeds Bradford, Aberdeen, Teesside, London City, Newcastle, Stansted, Manchester and Luton still at 100ml. Treat that as reporting, not an official register.
Some UK airports permit containers up to two litres under the relaxed procedure, and Aylesbury Airport Transfers has compiled which ones sit on each side of the line.
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The real risk is your connecting airport
The allowance you clear at Heathrow expires the moment you leave it. A transfer hub screens your bag again under its own rules. Plenty of them still cap containers at 100ml.
Singapore Changi is the clearest illustration. It turns away any container with a capacity above 100ml — even one that is barely filled — and the one-litre bag rule still applies there: one transparent resealable bag per passenger, capped at one litre in total.
A 500ml bottle that clears Heathrow without a second glance fails Changi on capacity alone, before anyone looks at how much is inside it. The same gap exists inside the UK: why Luton still caps liquids at 100ml despite having the same scanners is worth reading before you assume a UK connection is safe.
| Airport | Cabin liquid container limit | Clear plastic bag required | Laptops/electronics removed? | Verified-as-of date |
|---|---|---|---|---|
| Heathrow (Terminals 2, 3, 4 and 5) | Up to 2 litres per container | No | No; liquids and large electronics can remain in cabin baggage | October 2026 |
| Singapore Changi | 100ml maximum per container; 1 litre total in one transparent resealable bag | Yes; one closed bag per passenger | Not verified from the retrieved official page | October 2026 |
| Source: Heathrow; Changi Airport | ||||
Cabin versus checked baggage
Everything above governs cabin baggage. The container limit does not follow your liquids into the hold.
Checked baggage is screened differently and is not governed by the same container rule, which is why a full-size bottle of shampoo can travel in the hold on a trip where it would never clear security at the gate. The practical split is simple: if a liquid matters enough that you want it with you, it has to meet the cabin rule. If it only has to arrive, check it.
Why a scanner changed the rule, and why your bottle still matters
Old security screening produced a flat, two-dimensional shadow of your bag. Liquids and electronics had to be pulled out and separated because the machine could not tell a bottle of water from a dense cluster of cables. CT scanners build a three-dimensional image instead, rotating around the bag and reading density slice by slice. Once the machine can see inside a sealed container, the reason to empty it disappears.
Container construction is the exception. Metal reflects, and double-walled or vacuum-insulated flasks hold a layer of vacuum or air that the scanner reads as an obstruction rather than contents. The machine cannot confirm what is inside, so the rule reverts to the old logic: empty it, or lose it.
That is the whole mechanism in one line. The allowance is not a courtesy Heathrow decided to extend — it is a capability the equipment either has or does not.
What this means for you
The rules are settled; your itinerary is not. Three things are worth doing before you fly.
Check your onward airport. If your trip involves a transfer, or a return leg from somewhere other than Heathrow, look up that airport’s liquid rules directly. Heathrow’s own guidance points you there, and no central UK-wide tool compares airports in real time — the retrieved material turned up neither a working dashboard nor a published plan for one.
Pack for the stricter airport, not the looser one. If any leg runs through a hub still on 100ml, decant into small containers before you leave home. Repacking at a transfer lane is possible; it is also the moment you are most likely to lose something you wanted to keep.
Know what could change. A temporary scanner outage at a Heathrow terminal could push that terminal back to 100ml, and there is no verified instance of that happening in 2025 or 2026 — but the 2024 reversal shows how quickly a relaxed allowance can be withdrawn. If it happens, the fix is the same as anywhere else: containers of 100ml or less, in a clear bag.
Terminal differences are real, just not regulatory. Physical layouts, gate access times and peak-hour queue patterns still vary by terminal and airline, so the standard advice holds: three hours before a long-haul departure, two before short-haul.
Reporting by
Key terms
- Computed tomography scanners
- Computed tomography scanners are the security machines that build a three-dimensional image of a bag instead of the flat, two-dimensional shadow produced by older equipment. They rotate around a bag and read its contents by density, which is what allows sealed containers, laptops and large electronics to stay inside cabin baggage. That imaging capability is why Heathrow’s container limit could be raised at all — the rule changed because the equipment changed, not because the risk did.
- Department for Transport
- The Department for Transport is the UK government department that sets aviation security requirements, including the rules applied at airport liquid screening points. It writes those requirements, while each airport operator is the body that carries them out at the security lane. Because one writes the rule while the other applies it, passengers meet a national rulebook that produces a different answer at almost every airport they pass through.
- The one-litre bag rule
- The one-litre bag rule requires cabin liquids to travel inside a single transparent resealable bag whose total capacity does not exceed one litre. It sits alongside the older cap of 100ml on each individual container, and the two are normally applied together. Because the bag rule is applied at the security lane rather than at the point of sale or packing, it is the limit travellers tend to discover only when they reach the scanner.
Questions? Answers.
Has Heathrow scrapped the 100ml rule?
Yes, for departures and connections screened at Heathrow. Containers holding up to two litres are allowed at Terminals 2, 3, 4 and 5, clear plastic bags are no longer required, and liquids and large electronics can stay in cabin baggage. The 100ml limit can still apply at a connecting or return airport.
Do you still have to put liquids in plastic bags in 2026?
Not at Heathrow, where the clear plastic bag requirement has been dropped. Singapore Changi works the other way: nothing above 100ml gets through, and every container that does pass has to fit into a single transparent resealable bag holding no more than a litre.
Which airports no longer have the 100ml rule?
Heathrow is one, permitting containers up to two litres across all four terminals. A minority of UK airports also permit up to two litres under the relaxed procedure, while most still cap containers at 100ml.
Do you still have to put toiletries in a clear bag in 2026?
At Heathrow, no — toiletries can stay in your cabin bag without a clear bag. At airports still operating the 100ml rule, including Changi, a single transparent resealable bag is still required.
