Airport Security

For twenty years, the instruction at every US checkpoint was the same: shoes off, laptop out, liquids bagged. That rule quietly stopped being universal in July 2025. Airport security still runs on federal rules, but several of them changed in the last year.

The 3-1-1 liquids rule, stated exactly

Every liquid, gel, or aerosol in your carry-on needs a container of 3.4 ounces or 100 milliliters or less. All of those containers together have to fit in one quart size clear bag. That is one bag per traveler, no exceptions for a nearly empty bottle.

The number that trips people up is the one printed on the bottle. It is not the amount inside it. An 8 ounce lotion bottle fails even when it is almost empty, because the container itself is oversized.

Pack liquids into a small enough container, or check the bag instead. TSA officers are checking the label size, not the liquid level. Medically necessary liquids, including baby formula, are allowed over the limit if you declare them for separate screening.

Everything else over the limit gets left behind or checked at the counter. The 3-1-1 liquids packer tool checks a specific bottle against this rule in a few seconds. It is faster than guessing at the airport.

What comes out of your carry-on, and what stays in

At a standard lane, laptops and other large electronics come out of the bag. They go into their own bin for the X-ray. Your quart bag of liquids comes out too, and food often gets pulled for a closer look.

A TSA PreCheck lane changes this list. Laptops stay in the bag, and the liquids bag stays in the bag as well. Shoes, belts, and light jackets stay on too.

That is the actual value of PreCheck. It removes steps from the process, not the underlying rules about what you can carry. Item level questions belong on the can I bring pages, not here.

What comes off your body: the shoe rule that just changed

In July 2025, the Department of Homeland Security ended the blanket shoe removal rule at standard security lanes. This was not just a PreCheck perk anymore. Officials pointed to better scanner technology as the reason for the change.

The rollout was genuinely messy in its first weeks. Travelers reported keeping their shoes on at one airport, then removing them at another on the same trip. More than a year later the exemption is standard practice almost everywhere.

Officer discretion never went away, though. If your shoes alarm the metal detector, or you wear thick boots, removal is still possible. The same is true if you get pulled for extra screening at any point.

Belts with large metal buckles, and bulky jackets or coats, generally still come off in a standard lane. They are the items most likely to trigger a second look. A carry-on shoe bag is still worth packing for the plane itself.

Watches and jewelry have no blanket removal rule. Heavy metal pieces are a common source of false alarms, and TSA advises skipping them on travel days. See tsa.gov for the identification and screening standards this all sits under.

REAL ID and acceptable identification

Since May 7, 2025, TSA has enforced the REAL ID requirement on every domestic flight. Adult travelers need a REAL ID compliant license, a passport, a military ID, or another form from TSA’s accepted list. A plain, non compliant state license no longer works on its own.

A REAL ID card is marked with a star in the corner. Checking your own license takes about five seconds. Losing your ID before a flight is not automatically a disaster, either.

TSA has a process to verify your identity through other information if you show up without acceptable ID. Plenty of travelers still make their flight this way. The failure point is identity, not paperwork: if TSA cannot confirm who you are, you will not be allowed past the checkpoint.

PreCheck, Global Entry, and CLEAR: solving different problems

These three get confused constantly, and they are not competing versions of one thing. PreCheck speeds up airport security itself. It lets you skip the shoes, laptop, and liquids shuffle in a dedicated lane.

Global Entry speeds up something different: the customs line when you land back in the United States. CLEAR does not touch security screening at all. It replaces the document check at the front of the line with a biometric scan.

CLEAR gets you to the front faster, then hands you off to the same TSA screening as everyone else. Buying CLEAR without PreCheck still means unpacking your bag at the actual checkpoint.

Global Entry includes PreCheck as part of the membership. That is why frequent international flyers usually pick it over PreCheck alone. CLEAR stacks on top of either one, but by itself it solves an identity check problem, not an airport security one.

What airport security scanners actually see

The millimeter wave scanner at the checkpoint does not produce a photo of your body. TSA’s own description says the system detects potential threats automatically. It marks them on a generic outline that looks identical for every passenger.

There is no actual image to look at, because none is generated. False alarms are routine and rarely mean anything. AirTags, hair clips, sweat, and dense seams in clothing regularly light up the same outline as a real threat.

When that happens you get a targeted pat down of the alarmed area. It is done by an officer of the same gender, not a random full search. Plenty of travelers still believe the scanner shows a real body image, years after that older technology was phased out.

Where the rules get applied inconsistently

The honest answer is that airport security is a federal standard enforced by individual officers. Those two things are not always the same in practice. The shoe policy rollout is the clearest recent example of that gap.

Some checkpoints applied the new policy right away. Others kept the old habit for weeks after the announcement. Staffing, training timing, and individual officer judgment all shape what happens at a given lane on a given day.

The safest approach is to plan for the written rule and treat anything looser as a bonus. Keep your liquids bag accessible even in a PreCheck line. Equipment issues or staffing can bump you to standard screening without warning.

Run a full packing list through the list screener tool before a trip. It catches this kind of gap in advance, not at the checkpoint.

The bottom line

Airport security in 2026 is genuinely less annoying than it was a few years ago. The shoe rule finally caught up with the scanner technology. The core numbers, the 3.4 ounce liquid limit and the one quart bag, have not moved and are not likely to.

Where you still get caught out is inconsistency between checkpoints. Pack for the written rule, and treat anything faster as a pleasant surprise.