The short answer
Yes. Cologne and perfume are allowed in your carry-on in bottles of 3.4 oz (100 ml) or less, packed in your quart-size liquids bag. Larger bottles go in checked luggage, ideally wrapped and sealed in a plastic bag.
Carry-on vs checked bag
| Item | Carry-on | Checked bag |
|---|---|---|
| Bottle 3.4 oz (100 ml) or smaller | AllowedIn liquids bag | Allowed |
| Bottle over 3.4 oz (100 ml) | Not allowed | AllowedWrap and seal |
| Solid perfume / cologne stick | AllowedAny size | Allowed |
| Duty-free perfume (sealed bag) | AllowedIn tamper-evident bag with receipt | Allowed |
Is 3.4 oz the same as 100 ml?
Yes, for TSA purposes. 100 ml is 3.38 oz, and TSA writes the limit as 3.4 oz. A bottle labelled 100 ml is allowed; a 125 ml bottle is not, however little is left in it.
Duty-free perfume on connecting flights
Perfume bought at an international duty-free shop can stay in your carry-on if it is in a sealed, tamper-evident bag with the receipt inside, bought within the last 48 hours. If you connect in the US, keep the bag sealed until you clear the security checkpoint at your connection.
Packing full-size bottles in checked luggage
Perfume contains alcohol, so the FAA caps toiletries in checked bags at 18 oz (500 ml) per container and 70 oz (2 kg) total per person. Tape the cap, put the bottle in a zip bag and pack it in the middle of soft clothes.