CT scanners are expanding, airports are inconsistent, and travelers are confused. Here’s the honest, current state of the 3-1-1 rule — and what it means for your spring carry-on.
A traveler on Reddit’s r/AskTSA asked a question that dozens of others had already upvoted before she even got an answer: “I heard CT scanners mean I don’t have to follow the 3-1-1 rule anymore. Is that true?” The TSA officer who replied was polite but firm. The answer is: it depends on the airport, and assuming the rule doesn’t apply to you is how you end up throwing away a $40 bottle of face serum at security.
The 3-1-1 Rule: Still the Default
The 3-1-1 rule — liquids in containers of 3.4 ounces or less, all fitting in one quart-sized clear bag, one bag per passenger — remains the official standard for carry-on liquids across all U.S. airports as of April 2026. Nothing about the core rule has changed. What has changed is the technology used to screen those liquids at a growing number of airports.
CT (computed tomography) scanners create a three-dimensional image of bag contents, allowing TSA officers to identify liquids and other items with far greater precision than conventional X-ray machines. At airports with fully operational CT screening, TSA has the capability to clear liquids larger than 3.4 ounces without requiring passengers to remove them from their bags.
The critical word is “capability.” Having the capability and exercising it as a blanket policy are two different things.
Which Airports Have CT Scanners in 2026
CT scanners have been rolling out across major U.S. airports since 2019, and by early 2026 they are operational in some capacity at most large hub airports including Atlanta (ATL), Los Angeles (LAX), New York JFK, Chicago O’Hare (ORD), and Dallas-Fort Worth (DFW), among others.
However, deployment is uneven. Not every checkpoint at every terminal within these airports uses CT technology. A traveler who sailed through security with full-sized shampoo bottles at LAX’s Terminal 4 last month may face confiscation at a different terminal or on their return flight from a smaller regional airport.
The rule of thumb that Reddit’s r/AskTSA moderators repeat constantly: follow the 3-1-1 rule at all airports unless TSA staff at the specific checkpoint explicitly tell you otherwise. The cost of non-compliance — losing your liquids — is never worth the experiment.
What Has Genuinely Changed
A few meaningful updates are worth knowing for spring 2026 travel.
Medications in liquid form have always been exempt from the 3-1-1 rule in reasonable quantities, and this remains true. Declare them separately at the checkpoint and be prepared for additional screening. Baby formula and breast milk are similarly exempt and may exceed 3.4 ounces.
Duty-free liquids purchased after the security checkpoint — including at international transit airports — are subject to specific rules when connecting through U.S. airports. In general, they must be in a sealed tamper-evident bag with the receipt visible. This rule catches international travelers off guard more than any other liquids policy.
Powder-based products over 12 ounces (including protein powder, dry shampoo, and some cosmetics) require separate screening in carry-ons at U.S. checkpoints. This rule, introduced in recent years, is now consistently enforced and surprises a significant number of travelers who were previously waved through.
The Solid Alternatives That Solve the Problem Entirely
The cleanest solution to the 3-1-1 headache — and the one that Reddit’s packing community has embraced enthusiastically — is switching to solid and concentrated alternatives for your most liquid-heavy products.
Solid shampoo and conditioner bars have improved dramatically in quality over the past three years. Brands like Ethique, Lush, and Kitsch now produce products that outperform many liquid counterparts and eliminate the liquids bag entirely for hair care. Solid moisturizer bars, sunscreen sticks, and solid perfume balms extend the same principle to skincare.
For travelers who can’t or won’t switch, the practical solution is simple: check a bag, or ship toiletries to your destination. The cost of a checked bag on some routes is less than replacing premium skincare products confiscated at security.
Traveler’s Checklist: Liquids and TSA in April 2026
- Follow the 3-1-1 rule at all airports regardless of CT scanner rumors
- Use a clear, quart-sized zip-lock bag — don’t rely on a soft pouch that a TSA officer may question
- Place your liquids bag at the very top of your carry-on for fast, easy removal
- Declare all liquid medications separately and keep them accessible
- Switch to solid alternatives for shampoo, conditioner, and moisturizer to eliminate the problem
- Never assume your return airport has the same CT capabilities as your departure airport
- Powders over 12 ounces go in a separate bin — pack them at the top of your bag
- Duty-free liquids must be in a sealed tamper-evident bag with receipt when transiting U.S. airports
- When in doubt, pack it in checked luggage or ship it ahead
- Check TSA.gov before each trip — policies update and the official source is always current
The 3-1-1 rule is 20 years old and showing its age as technology improves. But in April 2026, it remains the law of the checkpoint at the vast majority of American airports. The traveler who respects it loses nothing. The one who gambles on a scanner upgrade they can’t confirm loses their conditioner in a trash bin at 5:45 a.m. The math is simple.