Is Peanut Butter A Liquid? Here's What The TSA Says

If you were planning on bringing your favorite supersized jar of Skippy in your carry-on through airport security, you might be wondering whether peanut butter counts as a solid, a liquid, or something in between. As it turns out, the TSA has given the question plenty of thought. In 2023, the agency put an end to the debate once and for all when it declared on X (formerly Twitter) that peanut butter is a liquid.

That means if the scanner finds the jar in your carry-on, be prepared for them to pull you aside for a very awkward chat about the reason you're trying to smuggle all-natural, extra-creamy peanut butter onto the plane. No matter what you tell them, though, in the end, you'll be given two choices: leave it with them to be disposed of later, or put it into your checked baggage.

If the ruling sounds absurd to you, you wouldn't be the only one to feel that way. However, the TSA has a very specific, unique definition of what a "liquid" is. According to spokesperson R. Carter Langston, in an email shared by the New York Times, the agency considers a substance a liquid: "If you can spill it, spray it, spread it, pump it or pour it." And since peanut butter is spreadable ... well, it fits the bill for a liquid! So, anyone who still wants to bring the nutty condiment with them on their flight will have to pack accordingly.

If you're dead set on having a jar of peanut butter in your carry-on to jazz up those famous Biscoff airline cookies, then the good news is that the TSA doesn't outright ban peanut butter in the cabin. So long as it conforms to the TSA's 3-1-1 rule, you can bring it with you to enjoy as you please without any issue. Specifically, the peanut butter has to be 3.4 ounces or less. Then it, along with any other liquids you intend to declare, has to fit neatly inside a 1 quart clear, plastic bag. Each passenger can carry one such "3-1-1 bag" in their carry-on.

Although you can technically measure and scoop out exactly 3.4 ounces of your favorite store-bought or homemade nut butter into an empty container, it's a lot more convenient (and safer) to buy peanut butter packed in travel-sized cups or small squeeze packs — lots of popular peanut butter brands sell them. Since they're pre-measured, you can confidently throw them in your 3-1-1 bag without having to worry about them getting thrown out at security.