Liquid Rules for 100mL Containers on Incheon Flights to Japan and Taiwan: How to Sort Cosmetics for Checked Baggage

When boarding international flights to Japan and Taiwan from Incheon International Airport, liquids and gels such as cosmetics and cleansers must be in containers of 100mL or less per container to be carried on board. Even if the remaining contents are small in amount, if the container's own capacity exceeds 100mL, it will be blocked from carry on and must instead be packed in your suitcase and checked as baggage.

At Incheon Airport security, 100mL is judged by container capacity

Incheon International Airport Corporation allows liquids, sprays, and gels on board only if they are placed in containers of 100mL or less and packed into a single clear resealable bag of 1L or less. The bag must measure 20.5cm x 20.5cm or 15cm x 25cm, and only one bag is allowed per passenger.

Here, the 100mL limit is judged by the container's own capacity, not the amount of liquid remaining inside it. Even if a 200mL skin toner bottle has only a small amount left, it cannot be carried on if the container's capacity exceeds 100mL.

The same rule applies to gel type toiletries and cosmetics such as cleansers, lotion, shampoo, and toothpaste. The list of items can be checked in the Incheon International Airport Corporation restricted items guide.

How to identify cosmetics and cleansers that must go into checked baggage

Cosmetics and cleansers in containers larger than 100mL must go into checked baggage without exception. Volumes frequently purchased during travel, such as a 300mL cleansing foam or a 200mL toner, are excluded from carry on.

Liquid medications exceeding 100mL may still be carried if you bring a doctor's note or prescription written in Korean or English, but only in the amount needed for use during the flight. Any remaining amount must be placed in checked baggage. Formula, baby food, and beverages for passengers traveling with infants and toddlers are also permitted only in the amount needed during the flight.

These exceptions are outlined in the Ministry of Land, Infrastructure and Transport's FAQ on liquid and gel carry on restrictions.

Items purchased at Incheon Airport duty free are an exception, but this does not apply on the return flight

Cosmetics purchased at duty free shops in the Incheon Airport departure area can be carried on board regardless of volume, provided they are placed in a Security Tamper Evident Bag (STEB) manufactured to International Civil Aviation Organization international standards, with the purchase receipt enclosed in or attached to the bag. This bag remains valid only if it stays unopened until boarding the flight to your final destination.

However, an STEB is valid only from the country of purchase to the country of final destination. Even if you purchase duty free cosmetics in Japan or Taiwan and have them packed in an STEB, you cannot carry that bag on board again for the return leg to Korea. It must instead be checked as baggage.

This is explained in Easy to Find Practical Legal Information, Purchase of Duty Free Liquid Products.

Departures from Narita and Kansai in Japan apply the same 100mL rule

Narita International Airport prohibits carrying on board liquids in containers exceeding 100mL (g). They are allowed only if divided into containers of 100mL or less and placed in a single clear resealable bag of 1L or less with sides no longer than 20cm. Resealable bags are not provided at the airport, so you need to prepare one in advance at a convenience store or household goods shop.

Kansai International Airport applies the same limit and bag specifications (no more than 20cm by 20cm, one bag per passenger). At both airports, liquids purchased at duty free shops inside the security area after completing departure screening are exempt from this rule.

The same 100mL rule applies again when transferring to an international flight within Japan, so if you plan to carry on cleansers or skincare purchased at a drugstore for your connecting flight, you need to check the container capacity again. Details can be found in the NAA Narita International Airport guide on international flight liquid carry on restrictions and the Kansai International Airport guide on restricted liquid items.

The 100mL rule for departures from Taoyuan, Taiwan

Taoyuan International Airport prohibits carrying on board liquids, gels, and sprays in containers exceeding 100mL. Containers of 100mL or less must be placed in a single clear resealable bag of 1L or less, with combined length and width not exceeding 40cm, and only one bag is allowed per passenger.

Medications or milk and food needed for infants and toddlers during the flight may be carried even if they exceed the volume limit, provided you explain this verbally to security screening staff and obtain their consent. Beverages and similar items purchased within the departure control area after passing security screening are not subject to this rule.

The procedure can be checked in the Taoyuan International Airport Security Check guide.

Summary of cosmetics and cleanser carry on conditions by airport

None of the three airports impose a volume limit on checked baggage, so cosmetics and cleansers in containers exceeding 100mL must go into checked baggage regardless of the departure airport.

Sources: Incheon International Airport Corporation, restricted items guide

Sources: Ministry of Land, Infrastructure and Transport, FAQ on liquid and gel carry on restrictions

Sources: Easy to Find Practical Legal Information, Purchase of Duty Free Liquid Products

Sources: NAA Narita International Airport, guide on international flight liquid carry on restrictions

Sources: Kansai International Airport, restricted liquid items

Sources: Taoyuan International Airport, Security Check