On a flight into the US with a connection, TSA lets duty free liquids over 3.4 oz through in the shop’s sealed tamper-evident bag, with the receipt, if you bought them in the last 48 hours. UK and EU airports also want the bag sealed with its receipt inside.
Where do you go through security again?
Duty free rule
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Or put it in your checked bag
TSA recommends packing liquids over 3.4 oz in your checked bag even when they’re in a sealed bag, because one that alarms or can’t be screened can’t stay in your carry-on.
Spirits in a checked bag follow the FAA’s alcohol limits: see alcohol on a plane.
Duty-free perfume
The FAA’s toiletry limits don’t apply to perfume and cologne bought from airport or airline duty-free shops and carried with you or in your carry-on. Customs rules generally limit how much you can bring in.
Common questions
What is a tamper-evident bag?
A tamper-evident bag is a clear bag the shop seals your purchase in. TSA's rule needs it packed by the retailer and showing no sign of tampering when you reach screening.
What if security opens the bag at my connection?
At EU airports, tell the security officer, so your liquids can be sealed in a new security bag for the next flight.
Can I open the bag on the plane?
No, UK and EU guidance says to keep it sealed until you reach your final destination.
Rules come from TSA, the FAA, the UK government and the European Union. Checked against published data from TSA, FAA, US DOT (eCFR), GOV.UK and European Union (plus 1 more).
See all 6 sources
TSA, Liquids, Aerosols, and Gels Rule (with its duty free exemption for inbound international flights)
FAA, PackSafe chart (printable, updated November 14, 2025): medical and toiletry articles, aerosols, alcoholic beverages, duty-free perfume
US DOT (eCFR), 49 CFR 175.10: exceptions for passengers, crewmembers and air operators
GOV.UK, Hand luggage restrictions at UK airports: liquids
European Union, Your Europe: luggage restrictions (last checked by the EU June 16, 2026)
European Commission, Mobility and Transport: liquids, aerosols and gels
General guidance from airline, TSA and FAA rules, checked on the date shown. Rules change, and the airline and security officers decide on the day: check your airline before you fly.