Airport Liquids Rules 2026: 100ml, CT Scanners & More

The liquids rule is nearly 20 years old, yet it still catches more travelers off-guard than almost any other security requirement. In 2026, the picture is more complicated than ever: CT scanner rollouts have eliminated the restriction at many UK airports, while the US TSA still enforces its 3-1-1 rule regardless of scanner technology. This guide covers the current rules region by region, what counts as a liquid, and how to pack toiletries so you never lose anything at the checkpoint again.

Why the Liquids Rule Exists

The restriction was introduced in August 2006 after UK intelligence services foiled a plot to detonate liquid explosives disguised as soft drinks aboard transatlantic flights. Within days, aviation authorities in the US, UK, and EU introduced emergency restrictions on liquids. What was meant to be a temporary measure hardened into international policy — the 100ml standard adopted by most countries is still in force today.

The underlying logic is that small volumes of liquid pose an acceptably manageable security risk, while larger volumes do not. CT scanners change this calculus because they produce a three-dimensional image of bag contents, allowing security software to analyse the density and composition of liquids — which is why airports with CT scanners can theoretically drop the bag requirement.

The US 3-1-1 Rule

The TSA's 3-1-1 rule applies at every US airport and has remained unchanged since 2006:

• 3.4 oz (100 ml) — the maximum container size. The container label must show 100 ml or less; a larger container that is only partially full does not comply
• 1 quart-sized bag — a clear, resealable zip-top plastic bag, approximately 20 × 20 cm (roughly one litre capacity). One bag per passenger
• 1 bag — removed from your carry-on and placed in a separate bin at the X-ray belt

The quart bag is a physical capacity check. Security officers may reject bags that are clearly larger than one quart, even if all containers are under 100 ml. A standard freezer zip-lock bag works fine; the TSA does not require a branded product.

CT Scanners at US Airports — No Exemption Yet

CT scanners are now deployed at checkpoints in most large US airports, including LAX terminals, JFK's Terminal 4, O'Hare, Atlanta Hartsfield-Jackson, Denver International, Dallas/Fort Worth, and many others. These machines produce detailed 3D images that are theoretically capable of screening liquids without the bag requirement.

Despite this, the TSA has not lifted the 3-1-1 rule. The liquid bag is still mandatory at all US airports. Travelers who pass through CT scanner lanes still need to remove their quart bag and place it in a bin. A policy change would require a formal regulatory amendment — which the TSA has not announced.

The UK/EU 100ml Rule

Outside the US, the standard is the same 100ml container limit, but the bag format varies slightly:

• Containers must hold 100 ml or less
• All containers must fit in a transparent resealable plastic bag of no more than 1 litre capacity (roughly 20 × 20 cm)
• One bag per passenger, removed from your carry-on at the checkpoint

This is functionally equivalent to the US 3-1-1 rule, though some EU airports are more relaxed about bag size and branding than TSA officers tend to be.

UK Airports That Have Removed the Restriction

The UK government began rolling out CT security scanners across major airports in 2022 and formally removed the 100ml liquids requirement at airports with approved CT lanes in 2024. As of mid-2026, passengers departing from full CT-equipped security lanes at these airports no longer need to remove liquids from their bags or comply with the 100ml limit:

• London Heathrow (LHR) — CT lanes operational across terminals
• London Gatwick (LGW) — CT lanes operational at South Terminal and North Terminal
• Manchester Airport (MAN) — CT lanes deployed across terminals
• Edinburgh Airport (EDI) — CT lanes operational
• Birmingham Airport (BHX) — CT lanes operational
• London Stansted (STN) — CT lanes operational
• Bristol Airport (BRS) — CT lanes operational
• London Luton (LTN) — CT lanes operational

Important caveats: not every security lane at these airports may be CT-equipped. If you're directed through a standard X-ray lane, the 100ml rule still applies. The safest approach is to pack liquids compliantly regardless — if CT lanes are available, you won't be stopped, and if you end up in a standard lane, you won't lose anything.

Smaller UK airports and those without CT approval still enforce the 100ml restriction fully.

What Counts as a Liquid

Security agencies apply a broad definition. The rule covers anything that flows, can be poured, squeezed, pumped, or spread. In practical terms:

Always treated as liquids:

• Water and all drinks (juice, coffee, alcohol, energy drinks)
• Shampoo, conditioner, body wash
• Moisturisers, serums, face creams, sunscreen (SPF lotion)
• Toothpaste (gels and pastes — all toothpaste is a liquid)
• Mascara, liquid eyeliner, lip gloss, foundation
• Gel and spray deodorants (solid stick deodorant is not a liquid)
• Hair gel, hair wax, mousse, dry shampoo spray
• Aerosols (hairspray, spray sunscreen, insect repellent)

Foods treated as liquids:

• Peanut butter, nut butters, hummus, guacamole
• Yoghurt, soft cheeses, jam, honey, syrup
• Soups, sauces, dips
• Ice cream, soft spreads

Not liquids (no restriction):

• Solid lipstick bullets
• Powder blush, eyeshadow, powder foundation
• Solid stick deodorant and antiperspirant
• Solid soap and shampoo bars
• Dry food items (nuts, crackers, sandwiches, fruit)

The "can you squeeze or spread it" test is the practical guide. When in doubt, pack it in your checked bag.

Duty-Free Exemptions (STEB Bags)

Liquids purchased airside — after you have cleared security — are exempt from the 100ml limit if they are in a Security Tamper-Evident Bag (STEB). All major airport duty-free shops seal purchases in STEB bags with the receipt visible through the bag. As long as the seal is intact when you board, bottles of wine, large perfumes, and spirits in STEB bags are permitted in the cabin.

The connecting flight problem: If your journey involves a connection where you must pass through security again, duty-free liquids become complicated. EU airports on non-Schengen connections frequently confiscate STEB-bagged duty-free from certain origins if the bag was purchased outside the EU. This is a known issue on routes like Dubai → a European hub → another EU destination. The safest approach on connections: buy duty-free at your final departure airport, not the first.

Medical Exemptions

Medically necessary liquids are exempt from the 100ml limit in the US, UK, and EU. This includes:

• Prescription liquid medications (antibiotics, antivirals, blood thinners)
• Insulin and insulin-related supplies
• Liquid supplements medically required
• Liquid nutritional products (for passengers with specific medical needs)
• Saline solution and contact lens solution in larger volumes (if medically declared)

At US airports, declare medical liquids to the TSA officer before screening begins. The officer will screen them separately — typically by swab or additional scanning. You do not need to place them in your quart bag. A prescription label or doctor's letter is not required by the TSA but is useful for large quantities or unusual medications.

At UK airports, the rules are similar: declare at the checkpoint, and you may be asked to show prescription packaging or a medical letter for quantities above what would be considered a standard travel supply.

Baby Formula, Breast Milk, and Infant Food

This is the clearest exemption. In the US, UK, and EU, parents travelling with infants may bring:

• Baby formula (liquid and powder)
• Breast milk
• Toddler drinks
• Baby food pouches and jars

All are exempt from the 100ml limit. Bring a reasonable quantity for the journey — "reasonable" is interpreted as proportionate to the length of travel, not a strict volume. You may be asked to open containers for additional screening (testing devices check for chemical content), but this is quick and routine. A boarding pass showing an infant on the booking is not required but can help if an officer questions large quantities.

What Happens If You're Caught with Oversized Liquids

If a security officer identifies a liquid container over 100ml in your carry-on:

• You will be asked to surrender it. There is no option to go back and pack it in your checked bag if you've already dropped bags
• The officer will not pour out the excess and return the bottle — the entire container is confiscated regardless of how full it is
• There is no fine for accidentally carrying liquids (it is not a criminal matter)
• Very expensive items (high-end perfume, specialty medications) are treated the same as cheap toiletries — the item is taken

The practical lesson: if you regularly lose the same item at security, pack duplicates. Travel-size toiletries in 30ml or 50ml containers eliminate the problem entirely.

Practical Tips for Packing Toiletries

Switch to solid alternatives. Shampoo bars, conditioner bars, solid moisturiser bars, and solid sunscreen sticks bypass the liquids rule entirely. A shampoo bar lasts as long as 2–3 bottles of liquid shampoo.

Invest in a dedicated toiletry bag. A clear PVC or nylon toiletry bag that zips flat makes airport security faster — just pull it out as one unit, not a collection of loose bottles.

Use travel-size containers rather than decanting into generic bottles. Containers with the original product labels are less likely to prompt questions about what they contain.

30ml bottles solve the maths problem. Three 30ml containers of three different products fit easily in your quart bag alongside toothpaste, deodorant gel, and face wash. Standard 100ml tubes tend to leave too little room.

Buy at the destination. For trips of a week or more, consider buying shampoo, conditioner, and body wash at your destination rather than packing them. Hotel toiletries handle the first night.

Know your airport. If you're departing from Heathrow, Gatwick, or another CT-equipped UK airport, your liquids bag is optional — but keep it accessible in case you end up in a standard lane.