Perfumes and colognes purchased through airport and airline duty free shops
Quantity limits: N/A — Because these are typically purchased at the airport or even on the aircraft, the quantity restrictions for toiletry articles do not apply here when purchased through Duty Free and carried on your person or in carry on baggage. However, quantities are generally regulated by customs/duty rules.
For perfumes and cologne in checked baggage or not purchased through duty-free sales, see the entry for Medicinal and Toiletry Articles.
See the regulation: 49 CFR 175.10(a)(5)