Type the size printed on the bottle, in fluid ounces or milliliters. TSA allows 3.4 oz (100 ml) a container in a carry-on, and UK and EU airports 100 ml.
Carry-on limits
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Common bottle sizes
Bottle sizes against the carry-on limits, as of October 2026
Size on the label
In the other unit
TSA carry-on
UK and EU hand luggage
1 fl oz
About 30 ml
Yes
Yes
2 fl oz
About 59 ml
Yes
Yes
3 fl oz
About 89 ml
Yes
Yes
100 ml
About 3.38 fl oz
Yes
Yes
3.4 fl oz
About 101 ml
Yes
Check the ml on the label
4 fl oz
About 118 ml
No
No
150 ml
About 5.07 fl oz
No
No
8 fl oz
About 237 ml
No
No
1 US fluid ounce is about 29.57 ml. TSA writes its limit as 3.4 ounces (100 milliliters).
Fluid ounces and milliliters
A US label gives the size in fluid ounces (fl oz) and often in milliliters too. UK and EU limits are in milliliters, so check the ml figure for those airports.
For a toiletry that’s too big, a refillable travel bottle of 3.4 oz (100 ml) or less lets you bring some in your carry-on. Medicine and baby liquids follow their own rules: see medication on a plane.
Common questions
Is 3.4 oz the same as 100 ml?
100 ml is about 3.38 US fluid ounces, and 3.4 fl oz is about 100.5 ml. TSA gives its limit as 3.4 ounces (100 milliliters).
How many travel bottles can I bring?
TSA limits each passenger to one quart-size bag of liquids, so the number is whatever fits in that one bag.
Carry-on limits come from TSA, the UK government and the European Union, and checked bag limits from the FAA. Checked against published data from TSA, FAA, GOV.UK, European Union and European Commission.
See all 6 sources
TSA, Liquids, Aerosols, and Gels Rule (with its duty free exemption for inbound international flights)
TSA, Frequently Asked Questions: Liquids, Aerosols, and Gels Rule
FAA, PackSafe chart (printable, updated November 14, 2025): medical and toiletry articles, aerosols, alcoholic beverages, duty-free perfume
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: information for air travellers
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.