15 years after an onboard bombing attempt led to restrictions on liquids in carry-on bags, limitations reman in effect in the United States and much of the world. But how many 3.4 ounce (100mL) bottles can you actually take onboard an airplane? The answer is surprising: quite a few, as it turns out.
How Many 3.4 Ounce Bottles Can I Take On My Flight?
According to the U.S. Transportation Security Administration, liquids in your carry-on bags are limited to:
- 3.4 oz (100ML) containers, inside
- 1 quart-sized bag
Restrictions go beyond pure liquids to include:
3.4 ounces is 100mL. Generally, I find that products in the USA are sold in 3 ounce containers, though do watch out – not all “travel sized” items are under 3.4 oz.
You can fit about 5-6 bottles inside a quart-sized bag along with other items like a comb, toothbrush, and razor. Depending upon how much you use and your hair length, 3.4 ounces of shampoo should last you for 3-4 hair washings. It’s another reason why I regret that hotels are abandoning individual-sized toiletries.
I travel at least 100,000 miles per year (often more than double that) and over the years I can count on one hand the number of times this has been closely enforced. In reality, I’ve never seen the TSA measure the dimensions of toiletry bags.
Tip: Use clear ziplock bags, which are less likely to draw scrutiny than opaque bags.
My point is simple: if you are traveling with carry-on luggage only, don’t worry if your toiletry bag is slightly larger. While it is a good idea to respect the maximum size limits for liquids, I’ve found the TSA has allowed slightly larger items (my deodorant, for example, is 3.5oz [103 mL] and technically over the limit, but always permitted) as well as slightly larger bags.
Furthermore, while you risk additional screening if you bring too many liquids onboard, the most important requirement is that the bottles are not too big.
Tip: If you choose to travel with extra liquids items, divide them into two quart-sized bags and place only one in each security screening bin. They will be less likely to be detected this way.
Exceptions To TSA Liquid Restrictions
Medications and infant/child “nourishments” (like formula) are excluded from the liquid ban. That includes bottled water if necessary to mix the formula.
Furthermore, duty free liquids purchased in the USA or aboard are permitted in carry-on bags if the following three conditions are met:
- The duty free liquids were purchased internationally and you are traveling to the United States with a connecting flight.
- The liquids are packed in a transparent, secure, tamper-evident bag by the retailer and do not show signs of tampering when presented to TSA for screening.
- The original receipt for the liquids is present and the purchase was made within 48 hours.
Do note that in my experience not every TSA agent seems well-versed in this rule, so if you do intend to transport duty free liquid, keep a copy of this page bookmarked or printed.
All other larger or excess liquids must be placed in checked baggage.
In my experience, 3.4 ounces (100mL) containers are more closely enforced than the size of the bag they are placed in. That said, even if you limit yourself to one quart-sized bag, that should be more than enough for your liquid needs.