Why You Can't Bring Peanut Butter Through Airport Security

The Transportation Security Authority, or TSA, is known for its super-specific and often strange rules when it comes to what you can bring through airport security. Frequent travelers know that you usually have to empty your water bottle before screening, since liquids above 3.4 ounces or 100 milliliters are a no-go, but there are some items that are treated the same way, but don't seem to be a liquid at all. One of these odd items is peanut butter.

Peanut butter may be thick, spreadable, and hardly close to something like water, but at a TSA screening, it's treated the same way as water, juice, or soap. If you're looking to bring a jar of the nutty spread through security, you might want to put it in your checked bag instead. Odds that are if it's not under that 3.4-ounce mark, a TSA officer will make you throw it out, eliminating your hopes for peanut butter and jelly pancakes or other peanut butter desserts. Most standard sized jars of peanut butter are way over the limit set by TSA — the smallest jar size sold by peanut butter brand Skippy is 16 ounces.

Some brands of peanut butter are more liquid-like than others, and "natural" brands might even have a layer of oil on top when you first open them. But peanut butter as a liquid? Something seems off here, and certain members of the TSA are willing to acknowledge it.

In a post to their official account on X, the TSA poked fun at their own rule, writing "You may not be nuts about it, but TSA considers your PB a liquid." They also wrote their definition of a liquid on an image attached to the message: A liquid has no defined shape, and simply takes on the shape of whatever container you put it in. For some kinds of peanut butter, this reasoning seems to make sense — think the runny spreads that are good for drizzling over oatmeal or yogurt bowls. But in other cases, the nut butter is more firm and set, holding its shape when scooped out of its container. At the end of the day, what the TSA says, goes — no matter how confused airline customers may be.

Even though the TSA tried their hardest to clear up all this peanut butter-based confusion, travelers are still finding this particular rule hard to understand. Some of the reactions to the TSA's tweet are pretty witty. One user commented that by the agency's logic, cats are also liquids, alongside images of cats squeezing themselves into tight spaces like vases or boxes. Others are (rightfully) confused by the general logic of what you can and cannot bring through TSA.

TSA's general list of rules about food products you can or cannot bring on the plane makes the distinction between liquid and solid even more convoluted. For example, fresh eggs can be brought in your carry-on bag with no restrictions, even though technically the inside of an egg is a liquid — and if a dozen fresh eggs were to break in your bag, you'd be dealing with quite lot of liquid. Other unconventional items that seem to fall under the liquid designation include hummus, jams and jellies, and salsa.