How big is a quart-size bag, and how strict is the TSA about it? This article covers the quart-size bag rules, the actual dimensions involved, and how much wiggle room the TSA really allows.
The TSA has specific guidelines for what can go through security in terms of travel-size container size and type, and the exact size of an acceptable quart-size bag is one of the most common questions travelers have. Here’s the full rundown.
How Big is a Quart-Sized Bag?
The TSA doesn’t enforce one exact required size for a quart-size bag, but it does describe the approximate dimensions as about 6 inches by 9 inches. A bag that’s a little larger than that generally isn’t a problem.
As a rule of thumb, if your bag’s overall dimensions (height plus length, roughly) don’t add up to much more than about 13-15 inches combined, you should be fine at the checkpoint.
Exceptions
There are a few exceptions to the standard quart-size bag rule. Breast milk, baby formula, and medically necessary liquids are allowed in reasonable quantities greater than 3.4 ounces (100 ml).
These items still need to be declared to a TSA officer at the checkpoint for separate screening. Larger containers that are less than half full are generally permitted too, and empty containers that once held liquids can go in your carry-on without restriction.
3-1-1 Rule
Keep the TSA’s 3-1-1 rule in mind when packing your quart-size bag. Each passenger can bring one quart-size bag of liquids, gels, creams, and pastes through the checkpoint in their carry-on. Each individual container inside that bag needs to hold 3.4 ounces (100 ml) or less.
All of it needs to fit in a single, clear, quart-size, zip-top bag, one bag per person. That bag can travel in either your carry-on or your checked luggage.
Bag sizes vary a bit by brand, but a standard quart-size bag runs roughly 7 x 8 inches.
TSA Liquids Rule
The TSA’s liquids rule exists for passenger safety and screening efficiency. It limits each passenger to liquids in containers of 3.4 ounces (100 ml) or less, all of which need to fit inside that one quart-size bag.
Using smaller containers and packing only what you actually need is the easiest way to make the most of that limited space.
How Strict is the Quart Size Bag?
The TSA isn’t especially strict about the exact size or style of the bag itself. As long as you’re not showing up with an oversized toiletry bag, a bag that’s a couple inches bigger than the stated dimensions generally isn’t an issue.
A standard quart-size Ziploc bag works fine too, just keep it reasonably close to quart-size rather than something noticeably larger.
Most toiletry bag manufacturers design their products to match the TSA’s stated dimensions specifically so they can market them as “TSA-approved,” so there’s a wide range of compliant options to choose from without much guesswork.
How Many Quart Bags Can You Take on a Carry-On?
The TSA allows just one quart-size bag per passenger in carry-on luggage, though there’s no limit on how many you can pack in checked luggage. Travelers who try to sneak two quart bags through carry-on screening are usually caught.
The good news: there’s no cap on how many individual travel-size containers you can fit inside that one bag, as long as everything fits and each container stays under the 3.4-ounce limit.
For example, if you want to bring 6.8 oz (about 201 ml) of shampoo total but can only use one bag, split it across two 3.4 oz (100 ml) travel bottles and pack both inside your quart-size bag.
Quart Size Bag Versus Sandwich Bag
Now that the basics are clear, here’s a quick comparison to help decide which type of bag works best for your liquids.
- Quart Size Bag: Purpose-built for travel, this is the ideal size for organizing 3-ounce toiletries before a flight. It fits the TSA’s quart-size guidelines exactly and holds a surprising amount for its size.
- Sandwich Bag: Originally meant for packing sandwiches and snacks, a sandwich bag is smaller than a quart-size bag but still clear-sided, so it can work as a backup TSA toiletry bag in a pinch.
Final Thoughts
The exact size of a quart-size bag can feel like a bit of a mystery, roughly 6 by 9 inches, but no TSA officer is going to pull out a ruler at the checkpoint. As long as your toiletry bag isn’t obviously oversized, you shouldn’t run into any issues.
Now that you know what the TSA actually expects from a quart-size carry-on bag, packing for your next trip should be a lot more straightforward.
Hello, I am Jan, a travel writer based in the Czech Republic. I specialize in discovering and writing about my homeland—medieval towns, mountain hikes, the local pub scene, and off-the-tourist-radar destinations.
I also write about life as an expat in Czechia—just what it is like to live here, and not just visit. I write sometimes about other countries from the region: Slovakia, Austria, Slovenia, and Croatia.
As an experienced traveler, I also give expert advice on travel, travel tips, and I often review travel gear.