Why are there TSA liquid restrictions on flights

We’ve become quite familiar with the routine of removing our 100ml liquid containers during airport security checks and then placing them into separate plastic bags as we pass through security checkpoints and you must have wondered why there are TSA liquid restrictions. However, 17 years ago, security allowed travelers to bring liquid containers of any size onto their flights.

Why are there TSA liquid restrictions on flights

One infamous case that led to liquid restrictions was the 2006 transatlantic aircraft plot. Terrorists planned to mix liquid explosives on board and detonate them mid-flight. This plot sent shockwaves through the aviation industry and the world and prompted a swift response from security agencies.

In the post-9/11 era, aviation security became a paramount concern. Intelligence agencies worldwide discovered a disturbing trend – terror attacks based on liquid explosives. One could mix and assemble these on board, making them difficult to detect.

What is the history behind liquid restrictions on flights?

Why are liquids limited on planes now, when the airport liquid policy allowed them 17 years ago? Here why –

  • During the investigation of the aforementioned case, authorities discovered a powdered soft drink and a bunch of batteries in the plotter’s baggage. 
  • This discovery raised alarm bells among authorities, leading to heightened security measures.
  • The plotters intended to deploy explosives using the liquid sippers for the in-flight detonation. 

What is the current airport liquid policy in 2023?

TSA continues to allow passengers to carry liquids, gels, and aerosols in travel-size containers, capped at 3.4 ounces as liquids on flights 2023. All these travel-size containers must fit inside a single quart-size bag.

Security checks – You should remove these liquids from your hand luggage and place them in one of the clear bags provided by airport security

Airport liquid Policy in 2023 – Passengers are limited to one bag per passenger that comfortably fits containers of 3.4 ounces or less in a one-quart-sized, clear, zip-top bag.

Please Note: Common travel items, like toothpaste, shampoo, conditioner, mouthwash, and lotion, must comply with the 3-1-1 liquids rule.

No liquid restrictions for checked baggage – There’s no liquid size limit for them. Feel free to pack those larger containers of your favorite shampoo or lotion in your checked luggage without worry.

Learn more about What is not-allowed on a plane carry-on?

TSA liquid restriction on flights for different liquid items

TSA liquid restriction on flights

Here are some liquid items for specific items as mentioned by the TSA under their liquid rules and regulations –

TSA liquid rules for hand sanitizer on flights

TSA permits the inclusion of hand sanitizer in a passenger’s carry-on bag, following the TSA liquids rule sanitizer. However, this allowance is subject to certain limitations. 

  • Travelers can only bring travel-sized hand sanitizer containers, with each container not exceeding 3.4 ounces (equivalent to 100 milliliters).
  • You can pack medicinal and toiletry items, including aerosols, as checked baggage. It should not surpass 2 kilograms (approximately 70 ounces) or 2 liters (about 68 fluid ounces). 
  • Ensure adequate protection with caps for aerosol release devices with buttons or nozzles that are permitted.

Can I bring mouthwash liquid on flights?

Each mouthwash container must not exceed 3.4 ounces (equivalent to 100 milliliters) in volume and must be placed within a transparent container along with other liquid items.

However, it’s worth noting that passengers have the flexibility to include mouthwash containers larger than 3.4 ounces in their checked baggage. 

These containers do not surpass the size limit set by the airline for carry-on bags

Can you carry cologne on flights?

TSA 3-1-1 rule for Cologne states that cologne can be considered carry-on baggage and must be in containers no larger than 3.4 ounces. If the limit is larger than that, each passenger’s combined quantity should not exceed 2 kg or 2 liters. 

TSA’s liquid rules regarding sunscreen on flights

As per TSA liquid rules sunscreen can be carried as a carry-on but they must each have a volume of 100 ml/3.4 oz or less.

If the liquid exceeds the amount, the airline might consider it as checked baggage. The total quality must not exceed 2 kg in your checked luggage. 

The TSA introduced these regulations under the category known as LAGs (Liquids, Aerosols, and Gels).

Is deodorant considered a liquid by TSA?

Yes, and TSA regulations restrict the inclusion of liquid containers exceeding 3.4 ounces in carry-on bags. Therefore, it’s essential to check the quantity specified on the container of your liquid or semi-liquid antiperspirant. 

For instance, numerous stick deodorants and antiperspirants are available in sizes below 3.4 ounces, making them suitable for carry-on luggage.


In conclusion, while liquid restrictions on flights may seem like an inconvenience, they are a necessary precaution to ensure the safety of air travel. The ever-present threat of liquid explosives demands strict measures, and the 3-1-1 rule is one such measure.

Frequently Asked Questions – FAQs

How many fluid oz can you bring on plane?

You can bring 3.4 oz (100 milliliters) or less per item on a plane as a carry on item.

Why do airports not allow liquid over 100ml on plane?

This rule helps prevent the mixing of liquid with explosives on board, which could pose a significant threat to the aircraft and the passengers. 

Is the TSA getting rid of the liquid rule?

TSA has confirmed that there are no changes in the liquid rule and the majority of airports have not made any announcements regarding the removal of the 3.4-ounce container limit for liquids in carry-on baggage.

Can I bring a 4 oz bottle on a plane if it’s not full?

No, the 3-1-1 rule typically applies to containers of liquids, gels, and aerosols that are 3.4 ounces (100ml) or less. If your container exceeds this limit, it may not be allowed through airport security.

Do you still need to put liquids in plastic bags for liquids on flights 2023?

Regardless of any updates, it’s important to note that all liquids must still adhere to the 100ml limit, be removed from your carry-on bag, and be placed inside one of the provided clear plastic bags.


Nancy James DP

Nancy James

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I am an aviation and travel enthusiast. Join me as I take you on a journey through the skies and share insights and interesting details about air travel. Here's you'll find me sharing the most captivating flight experiences and travel stories.

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