What Should Never Go in Checked Luggage

Almost everyone learns this list the hard way, one item at a time. The bag goes astray for two days, or arrives with a corner stoved in, and you discover which of your things you actually needed and which of them were never insured in the first place.

The rule underneath all of it is simple. A checked bag is out of your control from the moment it leaves the desk until it appears on the belt. It may travel on a different aircraft from you. It may be opened for inspection while you are not there. It may sit on a wet apron. None of that is unusual, and none of it is anybody behaving badly — it is just what checking a bag means.

So the question is not "what are the rules?" It is "what am I willing to be without for two days, and what would I be unable to replace?"

Things airlines will not let you check anyway

Start with the ones that are not a judgement call.

Power banks and spare lithium batteries have to travel in the cabin. This is a safety rule rather than an airline preference, and it exists because a battery fire in the hold is much harder to deal with than one in the cabin. Loose spare batteries, camera batteries and power banks all fall under it, and the exact allowances vary between airlines, so check the one you are flying with — we go through this properly in power banks and lithium batteries in luggage.

The same logic catches a few other things: e-cigarettes and vapes, and anything else with a lithium cell that is not installed inside a device. If you are unsure whether something counts, the airline's dangerous goods page will say, and it is worth two minutes at home rather than a conversation at the desk.

Medication, and anything you take on a schedule

This is the one that turns a delayed bag from an inconvenience into a problem.

Carry your medication in the cabin, in its original packaging, with enough to cover the trip plus a few extra days for a delay or a cancellation. If it needs a prescription or a doctor's letter, that goes in the cabin too, not in the suitcase with the medicine.

The same applies to spare glasses, contact lenses and solution, and to anything medical you rely on daily. If a delay would mean finding a pharmacy in a country where you do not speak the language, that item belongs with you. There is more on the documentation side in travelling with medication.

Documents, keys and the things that are irreplaceable rather than expensive

Passports and travel documents are obvious. The less obvious ones are the small items that cost very little and cause a great deal of trouble when they are missing.

• House and car keys. Losing these means arriving home at midnight and being unable to get in. They weigh nothing. Keep them on you.
• The card you are actually going to spend on, plus a second card kept somewhere separate.
• Anything with your home address on it. A bag tag with a full home address, or documents inside the bag, tells anyone who handles it that the house is empty. A phone number and an email address are enough on a tag.
• Physical tickets, event confirmations and printed reservations where a digital copy is not accepted.

None of these are valuable. All of them are hard to fix from another country.

Electronics and valuables

Laptops, cameras, tablets and phones should go in the cabin, for two reasons that stack.

The first is physical. A checked bag gets handled by machinery, dropped onto belts, and stacked underneath other bags. Cases are built to take that, and mostly they do — but the thing inside a laptop that breaks is not the case.

The second is the one people find out about afterwards. Airline liability for checked baggage is limited, and it is not designed to make you whole on high-value electronics or jewellery. Travel insurance policies typically limit or exclude valuables carried in checked luggage as well. Both of those are in writing before you fly — the airline's conditions of carriage, and your policy wording — and both are worth reading once, properly, rather than after a claim is refused.

If something is worth more than you would be comfortable losing, it does not go in the hold. That is the whole test, and it is a better guide than any list.

Sentimental things, which are the worst case

Jewellery you inherited. A camera you have had for twenty years. The only copy of photographs on a hard drive. Small artworks or gifts.

These are the items where compensation is irrelevant, because the amount you would be paid has nothing to do with what you lost. There is no insurance argument to have here — just keep them with you, or leave them at home.

Fragile things, and where the argument goes

Glass, ceramics, bottles and instruments are handled by the system exactly like everything else. Where fragile items are damaged in the hold, airlines commonly limit or exclude liability for them, which means a "fragile" sticker is a request rather than a guarantee.

If a fragile item genuinely has to travel, pack it so it survives being dropped from waist height, and accept that you are carrying the risk yourself. If it cannot survive that, it should be in the cabin or in a box travelling separately — sending bags ahead versus excess baggage covers when shipping is the better answer.

Liquids, and anything that can leak

This one is not about theft or loss. It is about the fact that the hold is not the same environment as the cabin, and things behave differently there.

Bottles that were sealed at sea level can weep at altitude. Sun cream, shampoo, oils, soy sauce, anything with a pump top or a screw cap that has been opened once — all of it is a candidate. The consequence is not just a ruined bottle; it is everything packed around it, and a suitcase lining that smells for a year.

The fix takes two minutes at home. Decant what you can into smaller sealed bottles rather than travelling with a large one. Put a square of cling film over the neck before screwing the cap back on. Bag anything liquid separately, and pack it flat and low rather than upright, because a bag lying on its side for eight hours does not care which way up you packed it.

The same thinking applies to anything that can stain: loose tea, spices, powdered anything. Sealed bag inside a sealed bag, and not next to the clothes you plan to wear on arrival.

If something valuable genuinely has to be checked

Sometimes there is no choice. The item is too large for the cabin, or the airline requires it in the hold, or your cabin allowance is already full.

In that case, do four things:

• Photograph it before you close the bag, and photograph the bag itself — outside and inside. A claim goes much better when you can show what was in there and what condition it was in.
• Ask at the desk whether the airline offers a declared value or excess valuation option. Not all do, and it usually costs something, but it is the only way to raise the liability limit if it exists.
• Keep the baggage tag receipt. It is the fastest route to a specific suitcase in a system holding thousands of them, and it is the first thing you will be asked for.
• Check what your travel insurance actually covers before you fly, not after — specifically whether valuables in checked baggage are limited, excluded, or covered only with a receipt.

None of that makes checking a valuable item a good idea. It just means that if you have to, you have done the things that make a claim possible rather than hopeless.

The practical version

You do not need to reorganise your packing around this. One small bag inside your cabin bag, packed with the same things every trip, covers almost all of it:

• Medication, prescriptions, spare glasses or lenses
• Passport, cards, keys
• Phone, laptop, chargers, power bank
• Anything irreplaceable
• One change of clothes and basic toiletries, for the two-day delay

That last line is the one people leave out, and it is the difference between a delayed bag being an annoyance and being a day spent shopping for socks. It is also the reason a cancellation feels manageable to some passengers and not others — the ones who are fine are simply the ones carrying that small bag.

Further reading: what to do in the first 24 hours when a bag is delayed, claiming for damage on arrival, and what actually happens to checked luggage in the hold. If you are rethinking how you pack, the VOX shop is here.

For the checked bags themselves, see why two travellers should cross-pack.

The same list decides what stays with you when a bag goes into left luggage for the day - see checkout at eleven, flight at midnight.