TSA's 3-1-1 Rule Explained: What It Is & How To Stay Compliant With It

We've all gone through it, even if we have TSA PreCheck or CLEAR. You need to catch an early morning flight, and in your haste, you forgot to finish that cup of coffee or bottle of water before going through the TSA security checkpoint. You then have to either chug the drink or throw it out. That way, you aren't pulled aside by the security officers and embarrassed in public. Even though we all know that we are limited in what liquids we can bring through security, it's easy to forget how much is allowed through. Well, the TSA has something called the 3-1-1 rule to help you keep your carry-on liquids down to a minimum.

The 3-1-1 rule has three different components to it, each corresponding to a number. The 3 refers to the amount of liquid you can have in a container, as it cannot exceed 3.4 ounces. However, you are not limited to one liquid container. The first 1 stands in for a quart-sized bag, and you can carry on as many 3.4 oz. or less containers of liquid that can fit in that bag. The second 1 refers to your carry-on luggage, as you can't have multiple of these quart-sized bags within a single piece of luggage. That seems simple enough, but it's not hard to end up falling short of the rule all the same.

The most obvious way to make sure you are complying with the TSA 3-1-1 rule is to head out to your local grocery store and purchase travel sized containers meant for 3.4 ounces of liquid or less that you can fill yourself. Whether it be shampoo, soap, conditioner, or whatever other essential item you might need for your trip, having a container that is designed specifically to adhere to this rule is a benefit. Going one step further, use an actual quart-sized bag to store them, rather than having them in some toiletry case that may be bigger than you thought. Some stores sell multiple travel-size bottles already in an appropriately sized bag.

Companies also manufacture their own travel-sized bottles for their liquid products, but this can be a bit misleading. Just because you find a small bottle of shampoo or aerosol can of hair mousse doesn't mean they are automatically good to go through security. Many of these containers are slightly larger than 3.4 ounces. In particular, 4-ounce bottles are abundant in those aisles designated for travel items. You might just think that you can use some before you go to get the actual amount of liquid in the container to meet the 3.4-ounce limit, but that will not do. If the actual container is meant for something that is over 3.4 ounces, it will have to be thrown away, put in checked luggage, or confiscated (to possibly be sold by the TSA later). We may not want to plan everything down to the smallest detail before a trip, but following the 3-1-1 rule will save you time to get through that body scanner without a hitch.