Your bag is almost never lost. It is separated from its paperwork, which is a different and much more fixable problem, and it usually catches you up within two days. Of the roughly 24 million bags mishandled worldwide in 2025, according to the air transport technology group SITA, the great majority were delayed rather than gone. Against five billion passengers that is fewer than five bags in every thousand, the best rate the industry has ever managed. It still costs airlines about 6.3 billion dollars a year, and it still ruins your week if you are one of the five.
The reason it happens at all is that the whole system depends on a machine successfully reading a strip of paper looped around a handle, and paper strips get crumpled, folded under, soaked and torn off. Thirty-nine per cent of mishandling in 2025 happened during transfers, where a bag has to leave one aircraft and find another in under an hour without ever being seen by a human. Here is the journey your suitcase actually takes, and the precise points at which it can slip out of the system’s sight.
The tag is a licence plate, not a record
When the check-in desk prints that long sticky strip, it is not writing your itinerary onto it. It prints a ten digit number, the bag’s licence plate, along with a barcode of the same number, your destination airport code and your flight. The first three digits identify the airline. The rest is a serial.
Everything else lives in a database. Your name, your connection, the aircraft your bag should be on, whether you have actually boarded. The paper does not know any of it. It knows who to ask. This is why a torn tag is catastrophic in a way that a torn boarding pass is not: without that number, a bag arriving at a sorting hall is genuinely anonymous, and staff have to open it and hunt for a name.
Down the rabbit hole
Behind the check-in desk your bag drops onto a belt and enters one of the most elaborate machines any of us regularly use without seeing. Heathrow’s Terminal 5 baggage system runs to roughly eleven miles of conveyor beneath the building, with bags travelling at speeds that would be alarming at eye level.
The first thing that happens is a scan. Not one scanner but an array of them, arranged in a ring so that a barcode facing in any direction has a chance of being seen. If they get it, the bag is routed automatically: through security screening, along the right branch, onto the make-up carousel for its flight, where a handler loads it into a metal container called a unit load device that goes into the aircraft hold.
If they do not get it, the bag is diverted to manual encoding, where a person looks at it on a screen or in the flesh and types the number in. That is the first place time is lost, and on a tight connection, time is the only thing that matters.
The read rate problem
Here is the number that explains most lost luggage. Optical barcode arrays in baggage halls typically read somewhere between 85 and 90 per cent of tags on the first pass. That sounds excellent until you multiply it out. One bag in eight needs human help, at every airport, on every leg.
The reasons are physical rather than clever. A barcode needs line of sight. Loop it around a handle and it curves, which distorts the stripes. Let it fold back on itself under the weight of the bag and it disappears entirely. Wrap the case in cling film at the airport, as many travellers do, and you have added a layer of glare. Soak it in rain on an open apron in Manchester and the ink runs.
Radio frequency identification, or RFID, solves exactly this. An RFID tag is a chip with a printed metal antenna that answers by radio instead of being looked at, so it does not care about orientation, folding, curvature or dirt. It has no battery: it draws the sliver of power it needs from the reader’s own signal. Read rates in baggage trials sit above 99 per cent. Our explainer on why UHF RFID dominates this kind of work covers the physics of that.
So why did it take airlines thirty years?
Because of a problem that has nothing to do with technology. An RFID bag tag costs pennies more than a paper one, and an airline handling a hundred million bags a year is looking at a serious annual cost. The awkward part is who gets the benefit.
Your bag’s most dangerous moment is a transfer, and a transfer usually involves somebody else’s airport and frequently somebody else’s airline. An airline that fits RFID tags to its own bags pays the whole cost while the savings land partly with competitors and hub operators. Everyone waits for everyone else. Economists call it a collective action problem. Aviation called it not this year.
Two things broke the deadlock. The first was Delta Air Lines, which in 2016 spent around 50 million dollars fitting RFID to its own operation across dozens of American airports, on the argument that a bag it could actually see was worth more than the tag cost. It worked, the tracking success rates were widely publicised, and other carriers stopped treating it as exotic.
The second was rules. IATA Resolution 753, which came into force in 2018, requires member airlines to track every bag at four points: when they take custody of it, when it is loaded, when it is transferred, and when it is returned to the passenger. It does not mandate RFID. It mandates knowing, which in practice pushes airlines towards whatever technology makes knowing cheap. Compliance passed the halfway mark across the industry only recently, which tells you how large a lift it has been.
Where it still falls over
Even a fully tracked bag can go astray, because tracking tells you where something is, not where it should be. A bag correctly scanned onto the correct aircraft is still wrong if you failed to board. A bag can be perfectly tracked into a container that misses its slot because the aircraft turns round in forty minutes and the crew ran out of time.
And then there are the days when the system itself falls over. When Heathrow’s Terminal 5 opened in March 2008, staff could not get through security or find parking, bags backed up, and the new baggage system was overwhelmed within hours. Thousands of bags went astray and more than five hundred flights were cancelled in the first ten days. Nothing was technically broken in the way people assume. The machinery worked. The humans and the processes around it had not been rehearsed at full load.
AirTags answer a different question
Plenty of travellers now drop a small Bluetooth tracker into the suitcase, and they are genuinely useful, but it is worth being clear about what they do.
An Apple AirTag or similar does not know where it is either. It shouts a coded identifier over Bluetooth, and any passing iPhone that hears it anonymously reports the location back. In an airport full of phones, that works beautifully. In an aircraft hold at 38,000 feet, or a rural sorting shed at three in the morning, nothing is listening and the location goes stale.
The real difference is who the information serves. Your tracker tells you your bag is still in Amsterdam. The airline’s system tells the airline which flight it should be put on next. For years those two facts sat in separate universes, with passengers standing at a desk insisting their bag was in Schiphol while an agent explained that the system had no record.
That gap has closed. Apple’s Share Item Location feature lets you generate a temporary link showing the tracker’s position and hand it to an airline, and 36 carriers now accept it, British Airways, Virgin Atlantic and Aer Lingus among them. The link expires after seven days or when you are reunited with the bag. It is a small feature that quietly ended a decade of arguments at baggage desks.
What actually helps
Book longer connections, because transfers are where 39 per cent of mishandling happens. Remove old tags from previous trips, because a stray barcode is exactly what a scanner will read confidently and wrongly. Photograph your bag before checking it, since describing a black four wheel case to a harassed agent is hopeless. Put a paper label with your name and destination inside, which is what staff look for when a tag is gone. And keep receipts for anything you buy while waiting, because delayed baggage expenses are usually claimable.
Frequently asked questions
How often do airlines actually lose bags?
Around 24 million bags were mishandled worldwide in 2025 against five billion passengers, which is fewer than five per thousand. Most of those were delayed and reunited within a couple of days. Permanently lost bags are a very small fraction of the total.
What is the most common cause of a lost bag?
Transfers. Thirty-nine per cent of mishandling in 2025 happened when a bag had to move between flights, usually in a short window and often between different airlines or airports.
Does RFID stop bags getting lost?
It removes the biggest single failure, which is a barcode that cannot be read. RFID tags answer by radio regardless of orientation or damage, pushing read rates above 99 per cent. It does not fix human or scheduling errors, so it reduces mishandling rather than eliminating it.
Should I put an AirTag in my suitcase?
It is genuinely useful, particularly for proving to an airline where your bag actually is. Just be aware that it relies on other people’s phones being nearby to report a location, so it goes quiet in aircraft holds and remote facilities.
What is IATA Resolution 753?
An industry rule in force since 2018 that requires airlines to track each bag at four moments: taking custody, loading, transferring and delivering. It does not specify a technology, but it made airlines invest in knowing where bags are rather than assuming.
What should I do the moment I realise my bag has not arrived?
Report it before leaving the airport and get a property irregularity report reference, since that number is what every later claim hangs on. Give a delivery address, share your tracker link if you have one, and keep receipts for essentials you have to buy in the meantime.
We explain the machinery behind ordinary life, without the jargon. Join the RFID News newsletter, or read more about tracking in logistics and transport.
