The sum is simple, and almost everybody gets it wrong the same way: they pack too few.
The arithmetic
One diaper for every hour of the total journey, plus four. Total journey means door to door, so add the taxi, the check-in queue, the gate wait, taxiing at both ends, immigration and the drive at the other side.
A six-hour flight isn't six hours. It's closer to eleven, which makes it fifteen diapers, and that gap is exactly how people end up buying diapers at Narita at four in the morning.
| Door-to-door | Example | Pack in cabin |
|---|---|---|
| 4-5 hours | Singapore to Bangkok, with transfers | 8–10 |
| 7-8 hours | Singapore to Tokyo or Sydney | 14–18 |
| 10-12 hours | Singapore to Dubai or Perth plus a long transfer | 20–24 |
| 14+ hours | Singapore to London or the US west coast | 28–30 |
| Any, with a connection | Add the layover hours | Count the waiting, not the flying |
Then add four more for a delay. Flights are held, connections are missed, and a bag with four spare diapers in it costs you almost nothing in space and buys you the entire difference between an inconvenience and a crisis.
Why every one goes in the cabin
All of them. None in the hold. Hold luggage gets delayed and lost, and you can't reach it during the part of the trip when you need diapers, so a diaper in the hold never helps you. They're light and bulky, so they cost you volume and no weight, and volume is the cheaper thing to spend. If you're travelling with somebody, split them across two bags. Little Rei's travel pack is eight pull-ups, so we put one sealed pack in each bag. If one of you gets separated from a bag, the other still has diapers.
The rest of the changing kit
Sized for the cabin, and organised so you can take a small part of it to the toilet instead of the whole bag.
- A slim changing mat, since aircraft tables are small and not always clean.
- Wipes in a resealable pack, plus a small pack in your own pocket.
- Wet bags or resealable bags, several, because there's often nowhere to put a soiled diaper immediately.
- Two changes of clothes minimum, and three for a long flight or a baby under six months.
- A change of top for you, which is the item everybody forgets and the one you'll most want.
- Barrier cream in a small pot, within the liquids allowance.
- A muslin, or two.
- A pre-packed pouch with one diaper, a few wipes and a bag in it, so a change is one item out of the bag and not an excavation in an aisle.
The arithmetic elsewhere
When there's no changing table
Some aircraft toilets have a fold-down table, and on most planes it's one or two of them. Ask cabin crew which ones as soon as you board.
Where there's none, the options are a mat across the closed toilet lid, or on your own lap in your seat for a wet one, which is entirely acceptable and which everybody around you has either done or will do. Ask a member of crew. They deal with this all the time and are more relaxed about it than the internet suggests. I can't remember a single crew member being anything other than kind about it. One brought a blanket.
Change her before boarding, whatever the state of the diaper. It buys you the whole taxi and take-off period, which is the stretch when you can't get up.
The part that isn't about diapers
Two things count for more than the diaper count and neither is obvious the first time.
The first is ears. Feeding, a bottle or a dummy during descent helps her equalise pressure, and descent is the part that hurts. Don't let her sleep through the descent if you can help it. Waking her feels cruel, but it's kinder.
The second is the air. Cabin air is extremely dry, so offer fluids more often than you would on the ground, and dress her in layers, because a cabin runs cold and the temperature change on landing here is about fifteen degrees.
We fly to see family with two small children and I've never once regretted overpacking the diapers. I have regretted the opposite.
Read next
What other parents wanted to know
How many diapers should I pack for a flight?
One per hour of door-to-door travel, plus four for delays. A seven-hour flight with transfers means around fourteen to eighteen in the cabin bag.
Should diapers go in hand luggage or the hold?
Hand luggage, all of them. Hold bags are unreachable during the journey and are delayed often enough that arriving with none is a real scenario.
Do you count the airport time when packing diapers?
Yes. Count door to door: the journey to the airport, check-in, the flight, and the wait at the far end. That's usually four more diapers than flight time suggests.
What if the plane has no changing table?
Ask the crew, who often know of one specific lavatory or can offer a galley area. Failing that, a wet change on your lap on a folding mat is normal.
Do babies need more diaper changes on a plane?
Change more often, never less. Dry cabin air plus a long stretch in one diaper is a common cause of rash appearing at the far end of a trip.
What I read for this
This guide is general information, written to help you understand a topic and ask better questions. It is not medical advice and does not replace your own doctor, midwife or paediatrician. Anything that worries you about your baby belongs with them.