Airline Baggage Allowances Explained: Carry-On & Checked Limits
Baggage fees are the travel expense that is easiest to avoid and most often paid anyway. The reason is almost always the same: a bag that looked fine at home turns out to be a centimetre too tall or a kilo too heavy for the airline at the gate. Here is how airline baggage allowances actually work.
Carry-on versus checked: two different rule sets
Every airline splits baggage into carry-on (the bag you take into the cabin) and checked (the bag you hand over at the desk). Each has its own size, weight, and piece limits, and the two are not interchangeable. A bag that qualifies as carry-on on one airline may be forced into the hold on another.
The key insight: allowances are set per airline, per route, and per fare — not by a single global rule. The only reliable approach is to check the specific airline and ticket you are flying on.
Carry-on limits: size, weight, and the sizer
Carry-on rules usually combine a maximum dimension (length × width × depth in centimetres) and a maximum weight. Full-service airlines commonly allow something close to 55 × 35 × 20 cm with a weight around 7–10 kg. Low-cost carriers are frequently stricter — sometimes a smaller sizer, sometimes a 7 kg cap that is actually enforced, and sometimes a basic fare that only includes a small under-seat bag with carry-on as a paid extra.
Personal items (a small bag or laptop case under the seat) are usually allowed in addition, but again the size rules vary. If your carry-on is close to the limit, expect it to be checked in a sizer at the gate.
Checked baggage: weight, pieces, and fare class
Checked allowances are usually expressed as a weight limit (commonly 20–23 kg for a standard economy bag on long-haul full-service flights) or as a piece concept (one or two bags up to a weight each). Crucially, many cheaper fares — especially "light" economy or low-cost tickets — include no checked bag at all, and you must buy one separately.
Going over the weight limit triggers an excess fee that is almost always much higher at the airport than online. If you think you might be close, buy extra allowance in advance.
How low-cost carriers change the game
Budget airlines built their model on unbundling — the headline fare is low because almost everything is extra. That includes carry-on beyond a small personal bag, seat selection, and checked bags. A "cheap" ticket can end up costing more than a full-service one once baggage is added. Always compare the final price including the bags you actually need.
A worked example
Suppose you fly a low-cost carrier with a basic fare that includes only a small under-seat bag (40 × 20 × 25 cm). You plan to bring a standard roll-aboard carry-on. On a full-service airline that bag might be free in the cabin; here it is a paid extra, and if you turn up without pre-paying, the gate fee is higher. Checking the Baggage Checker beforehand shows the exact dimensions and weight cap, so you buy the right allowance online and avoid the gate penalty.
Practical tips to stay within your allowance
- Weigh your bag at home. Bathroom scales catch the kilo you would have missed at the desk.
- Measure soft bags packed full. A bag that meets the limit empty can bulge past it when stuffed.
- Buy extra allowance online. Airport excess fees are always higher.
- Watch your liquids. Carry-on liquid limits are separate from size — see our 100ml liquids guide.
Frequently asked questions
What is the standard carry-on size limit for airlines?
There is no single global standard. Many full-service airlines allow roughly 55 x 35 x 20 cm, but low-cost carriers are often stricter and may include a smaller sizer or a weight cap as low as 7 kg. Always check the specific airline's carry-on limits before you pack.
How much does checked baggage usually weigh?
A standard checked bag allowance is commonly around 20 to 23 kg on long-haul full-service flights, with economy light fares sometimes including no checked bag at all. Weight and piece allowances vary by airline, route, and fare class, so confirm your specific ticket's allowance.
Do low-cost airlines have different baggage rules?
Yes. Low-cost carriers often charge extra for carry-on beyond a small under-seat bag, enforce stricter size and weight limits, and sell checked bags as add-ons. What is free on a full-service airline may cost extra on a budget one.
What happens if my bag is over the size or weight limit?
You will usually be charged an excess baggage fee, which is almost always more expensive at the airport than online. In some cases an oversize carry-on may be moved to the hold. Weigh and measure your bags at home and buy any extra allowance in advance to save money.
Check your airline's baggage limits
Look up carry-on and checked size and weight limits for major airlines before you pack — no account needed.
Open the Baggage CheckerThis article is general travel guidance. Baggage allowances vary by airline, route, fare class, and frequent-flyer status and change over time. Always confirm the exact allowance for your specific ticket with your airline before you travel. Written by the PlanTrippr team and not sponsored by any third party.