TSA’s 3-1-1 Liquids Rule: What to Know

Whether you’re flying to your destination or headed home, you might have non-solid items in your carry-on bag. Items can range from personal hygiene products — like shampoo or contact lens solution — to consumable souvenirs from your trip, like a mini bottle of rum from the Caribbean.

However, remember the Transportation Security Administration’s (TSA) 3-1-1 liquids rule when packing your carry-on luggage. This guideline states how liquids must be stored in the bag you take onboard, and enforces volume restrictions for liquid items.

Learn why it is called the 3-1-1 rule, and how to pack carry-on liquids effectively for a streamlined travel experience.

What is the TSA 3-1-1 liquid rule?

In September 2006, the TSA implemented the liquids restriction that travelers flying in and out of U.S. airports know today. The guideline is called the 3-1-1 liquids rule, which is meant to help passengers easily remember the rules for liquid in carry-on bags.

So, why is it called the 3-1-1 rule? Here’s what each number means:

• 3: Passengers can bring up to 3.4 ounces (“3” for simplicity) of liquid. This measurement also equates to 100 milliliters per container.

• 1: All liquid containers must fit into 1 quart-sized bag.

• 1: Only 1 quart-sized bag is allowed per passenger.

The TSA’s 3-1-1 rule applies to liquids, including gels, creams, pastes, aerosols, and consumable goods, like salsa, honey, and peanut butter.

Understanding the 3-1-1 liquids guidelines

Despite the easy-to-remember 3-1-1 liquids rule, there are a few details that some travelers might feel are open to interpretation. Here’s more clarification about the TSA’s guidelines.

The first thing to consider when bringing liquid in your carry-on bag is its container. According to the TSA, the size of the container is used to determine the amount of liquid.

For example, if you have a partially consumed sports beverage bottle that’s labeled 16 ounces, but only have 3 ounces of liquid left, this doesn’t follow the 3-1-1 rule. The container’s volume exceeds the allowable 3.4-ounce volume limit and isn’t cleared to go through TSA checkpoint.

Additionally, all liquid containers must be put inside a clear, quart-sized resealable bag. Other bags, like clear, vinyl travel toiletry pouches with a zippered top, are also acceptable.

Finally, remove the liquids bag from your carry-on luggage when preparing your belongings for TSA checkpoint screening. They must be placed in a bin for review.

If you have TSA PreCheck, a membership program operated by the TSA, you do not have to remove your liquids bag at screening, but its contents must still follow the 3-1-1 rule.

TSA PreCheck offers dedicated airport security lines and streamlined screening at a few hundred airports across the U.S. Membership lasts five years and costs $78-$85, depending on where you enroll.

However, you can join the program without paying out-of-pocket as it is an included benefit of many travel credit cards.