A small strip of paper attached to a passenger’s suitcase at the airport carries a number that helps identify the bag as it moves through the baggage-handling process. Printed alongside a barcode on the tag is a 10-digit licence plate used under international baggage standards to identify checked luggage.
The 10-digit licence plate is covered by Resolution 751 of the International Air Transport Association (IATA). It consists of a leading digit followed by a three-digit baggage tag issuer code and a six-digit serial number together they provide a standardized identification number for the bag.
The number is also printed in machine-readable barcode form which scanners and baggage-handling equipment can read the barcode as the suitcase moves through the airport. This allows the bag to be identified without relying only on the passenger’s name or the appearance of the suitcase.
Once the bag is accepted at check-in the identification becomes part of the information used to process it then the bag can be identified during sorting and loading as it is prepared for the passenger’s flight. The same identification can also be used when the bag has to be handled at another point in the journey.
Standardisation becomes more important when a passenger has a connecting flight a checked bag may move from one aircraft to another or pass through another airport before reaching its final destination, using a standard baggage identifier allows the different baggage-handling systems involved in the journey to refer to the same bag.
The 10-digit licence plate is not the same thing as baggage tracking. IATA has a separate standard for tracking baggage under Resolution 753. The tracking standard sets out requirements for recording the bag at specific points in its journey so that airlines can know where it has been handled.
IATA requires baggage tracking at four key points when the airline receives the bag from the passenger, when it is loaded onto the aircraft when it is delivered to the transfer area for a connecting journey and when it is returned to the passenger at the destination. These records provide information on the movement of the bag during the journey.
The need for reliable baggage handling is clear from the number of bags that are still mishandled each year. IATA reported that airlines mishandled 33.4 million bags in 2024, equivalent to 6.3 bags for every 1,000 passengers mishandling includes bags that are delayed, damaged, pilfered or lost.
The number printed on a baggage tag may therefore look ordinary to a passenger checking in for a flight but it serves a defined purpose within the wider baggage-handling process. Once the suitcase leaves the check-in counter the 10-digit licence plate gives the bag a standard reference that can be read and used as it moves through the journey.







