Tips

Baggage Weight and Carry-on Rules at a Glance: Liquids, Power Banks and Excess Fees

Bag allowances depend on your airline and fare. Where to check them, the near-universal rules for liquids and power banks, and how to avoid excess baggage fees.

Suitcases travel around a baggage carousel in an airport arrivals hall. — Airport baggage carousel · Photo: Stolbovsky / CC BY-SA 3.0

Published 2026-09-30 · Updated 2026-10-01

Your allowance depends on your ticket

How many checked bags you get, how heavy they can be, and the size and weight limit for carry-on bags vary by airline, fare type, cabin class and route. Even on the same airline, the cheapest fares may not include a checked bag.

So check your booking confirmation (e-ticket) and the airline's official baggage page rather than numbers you find online. The confirmation shows your baggage allowance in kilograms or pieces. On connecting or multi-airline trips, the rules can differ for each flight, so check every segment.

Low-cost carriers: add bags early

Many low-cost fares do not include checked bags. Adding one at the airport is often more expensive than buying it in advance, so add bags in the airline's app or website when you book or before you fly.

Some airlines also measure and weigh carry-on bags. If your fare allows only one small bag, a handbag or shopping bag may count toward the limit, so read the rules carefully.

Liquids: 100 ml containers, one 1-litre clear bag

As a general rule (for example under Korea's aviation security standards), liquids, gels and aerosols in your carry-on must be in containers of 100 ml or less, all fitting in one clear resealable bag of up to one litre. A 150 ml container is not allowed even if it is almost empty. Pack larger toiletries in your checked bag, and check the official airport or aviation security guidance before you fly.

Baby food, formula and necessary medicines can usually be carried in reasonable quantities; take them out at security. Some airports with newer scanners apply different rules, so check the rules at your return and transit airports too.

Keep duty-free liquids in the sealed bag with the receipt
Duty-free liquids can be confiscated at transit security checks — check the transit airport's rules
Toothpaste, contact lens solution and hand cream count as liquids

Power banks and electronics: carry them on

Power banks and spare lithium batteries are not allowed in checked baggage; they must go in your carry-on. According to the Korean government, from 20 April 2026, in line with the international standard, passengers may carry at most two power banks and may not charge or use them on board. On flights from Korea they also may not be stored in the overhead bin, so keep them on you. Depending on capacity (Wh), a battery may be refused or need airline approval, so check the capacity printed on it and the official government, airport and airline guidance before you fly.

Carry laptops, cameras and other devices with batteries in the cabin where possible; if they must be checked, switch them off completely. E-cigarettes generally cannot be checked or used on board.

Knives, sprays and food

Knives, long scissors and tools are not allowed in the cabin and belong in checked baggage. Rules for lighters, matches, aerosols and fuels vary by country and airline, so check your airport's and airline's guidance before packing them.

Flying with food and bringing it into another country are separate questions. Many countries restrict meat products, fruit and seeds at customs, and undeclared items can mean fines. Check the destination's official biosecurity or customs guidance first.

Avoiding excess baggage fees

Excess weight at the airport can be expensive. Weigh your bags at home with a luggage scale and leave room for souvenirs on the way back.

When traveling with others, spread heavy items across bags so none goes over the limit, and wear your heaviest shoes and jacket on board. If you expect extra luggage, buying additional allowance in advance is usually cheaper than paying at the counter.

Baggage checks, step by step — Before you go: check the baggage allowance on your booking and the carry-on rules / When packing: liquids in 100 ml containers in a 1-litre bag, power banks in your carry-on / Before the airport: weigh bags at home and leave room for the return trip / At your destination: check food and customs rules — Diagram: OneWorld (based on this article; times are approximate)

Before you go: check the baggage allowance on your booking and the carry-on rules
When packing: liquids in 100 ml containers in a 1-litre bag, power banks in your carry-on
Before the airport: weigh bags at home and leave room for the return trip
At your destination: check food and customs rules

FAQ

How much checked baggage is free?

It depends on the airline, fare, cabin and route. Check the allowance on your booking confirmation and the airline's official baggage page.

Can I put a power bank in my checked suitcase?

No. Power banks and spare lithium batteries must travel in your carry-on. Check your airline's capacity and quantity limits.

What about toiletries over 100 ml?

Put them in your checked bag. Carry-on liquids generally need containers of 100 ml or less in one clear bag of about one litre.

Is duty-free alcohol safe on a connecting flight?

Even in a sealed bag with the receipt, it can be confiscated at transit security. Check the transit airport's rules in advance.