One-Bag Travel: How to Pack Light Without Suffering

The point of one bag is not minimalism for its own sake. It is stairs, buses and last-minute changes of plan. Here is the system, and the cases where checking a bag is the better choice.

8 min read · 27 October 2026

Travel with a single carry-on and you skip the check-in queue and the baggage carousel, and you cannot lose your luggage because it never leaves your hands. That is the headline. The real benefit shows up later, at the foot of a flight of stairs in an old town with no lift, or when a cheap early bus leaves before the hotel has finished breakfast. A wheeled suitcase on cobbles is a small daily argument. A backpack is not.

Why one bag: it is about stairs, not minimalism

Travel with a single carry-on and you skip the check-in queue and the baggage carousel, and you cannot lose your luggage because it never leaves your hands. That is the headline. The real benefit shows up later, at the foot of a flight of stairs in an old town with no lift, or when a cheap early bus leaves before the hotel has finished breakfast. A wheeled suitcase on cobbles is a small daily argument. A backpack is not.

It also forces a useful question about what you actually need. Most people discover the answer is about half of what they were going to bring. Not everyone should go this way: if you are carrying work equipment, dressing for a wedding, travelling with small children or heading somewhere properly cold, a checked bag is a sensible choice. One bag is a tool, not a creed.

Check the bag limits first, because airlines disagree

Cabin allowances vary widely and are tightest on low-cost fares, where some tickets include only a small under-seat bag and charge for anything larger. Many airlines also set a weight limit, commonly between 7 and 10 kg, and some enforce it at the gate. Read the current rules for each airline on your route before you buy a bag, and measure the bag you own against them. The list below is built for 7 kg, which fits most limits, but yours may differ.

Most one-bag travellers end up with something between 30 and 40 litres. Smaller is possible, but it demands a very short list and regular laundry. Pack the heavy items close to your back, put what you need in flight on top, and wear your bulkiest shoes and jacket through the airport.

The 7kg capsule: the 5-4-3-2-1 rule

The rule is a counting system for clothes that mix with each other. Five tops, four bottoms, three layers, two pairs of shoes and one wild card. Underwear and socks sit outside the count: five pairs of underwear and three pairs of socks. Choose two or three colours so everything goes with everything, and the 15 items make well over a dozen outfits.

• 5 tops: three T-shirts or short-sleeved shirts, one long-sleeved top, one smarter shirt for evenings.
• 4 bottoms: two pairs of trousers, one pair of shorts or a skirt, one pair of lightweight leggings or joggers for sleeping, flying and travel days.
• 3 layers: a warm mid-layer such as a fleece or merino jumper, a packable shell that blocks rain and wind, and a light spare layer, such as a cardigan or overshirt.
• 2 pairs of shoes: one worn-in pair for walking, worn on the plane, and one light pair of sandals or flats that also works as slippers and shower shoes.
• 1 wild card: swimwear, a dress, a scarf or a hat. Choose the thing your trip will actually need.

Merino layering: why it earns its price

Merino wool can be worn several days before it smells, regulates temperature across a wide range, and dries overnight. Synthetic tops dry quickly too, but they hold odour sooner. A mix is fine. A cotton T-shirt is not a crime, but it dries slowly, and in humid weather that matters.

Think in three thin layers rather than one thick one: a merino or synthetic base against the skin, a mid-layer for warmth, and a shell for wind and rain. You can add or remove one layer as the day changes, and the three together weigh less than a single heavy coat. Wash something every three or four days. Merino is dearer than cotton, often $51–76 (£40 to £60; ≈ €45–70) a top at the time of writing, so buy one or two and fill the rest with synthetics, then add more only if the first ones prove themselves. Check the care label: merino hates a hot dryer, and a wool-and-nylon blend is more durable than pure wool for a bag that gets squashed daily.

The sink-laundry kit

A sink and ten minutes replace half your wardrobe. The kit weighs about 100 g and fits in a pocket:

• A universal flat sink plug, because many basins have none.
• A bar of laundry soap or a few travel detergent sheets.
• A length of braided elastic cord for a washing line, or a few pegs.
• A quick-dry microfibre towel for rolling clothes to squeeze out the water.
• Method: wash in warm water, rinse twice, roll in the towel, and hang overnight. Do it in the evening and everything is dry by morning.

Liquids and electronics: organise by pouch

At most airports, liquids in hand luggage must still be in containers of 100 ml or less, inside a clear bag. A few airports have relaxed this with newer scanners, so check the departure and the return airport rather than assuming. For anything beyond a week, buy full-size shampoo and toothpaste when you arrive. Solid shampoo and soap bars sidestep the liquids rule and last for months. Keep prescription medicines in original packaging, and check the destination's rules on common medicines.

Take a phone, a charger, one universal adapter and headphones. An e-reader weighs under 200 g and replaces a kilo of paperbacks, which is the best exchange in this whole article. Power banks must go in your cabin bag, never the hold, and airline rules generally cap them at 100 watt-hours, roughly 27,000 mAh. Use two pouches: a clear one at the top of the bag for liquids, and a small one for cables, adapter and power bank, so security takes thirty seconds.

Winter versus tropical: what changes

The capsule flexes with the climate, but the weight does not. For the tropics, swap the warm layer for a second shell-weight top, bring a rain jacket rather than a coat, and choose loose, quick-dry cloth. Add reef-safe sun cream bought on arrival, and sandals you can walk in. Humid climates change the laundry maths: cotton takes a day or more to dry, so lean on synthetics and merino and wash every other day. Pack a small dry bag for the phone, passport and cash on boat days.

For winter, the problem is bulk, not weight. Wear the coat and the boots through the airport. Pack thermal base layers in merino, a hat and gloves, and drop the shorts and the spare shirt. If you cannot reach 7 kg with a proper winter coat, a checked bag is the honest answer.

The weight budget, and leaving a gap

Roughly, as a guide: bag 1.0 kg, clothes 3.0 kg, second pair of shoes 0.6 kg, toiletries 0.5 kg, electronics 1.0 kg, documents and small kit 0.4 kg, laundry kit 0.1 kg. That is 6.6 kg and leaves a margin. Weigh the packed bag on bathroom scales.

Pack in a fixed order so you can find things in the dark. Shoes and the heaviest items go at the bottom, against the back panel. Clothes go in the middle, rolled or folded into one or two packing cubes, one for clean and one for worn. The shell, the pouches and your documents go on top, where you can reach them without unpacking. Keep a small day bag or a foldable tote inside the main bag for market trips and day walks, and count its weight in the 7 kg.

Do a dry run. Carry the packed bag around the block for twenty minutes, then up and down a flight of stairs. If you resent it before you leave the street, you will resent it in Lisbon. Take out the one item you reached for least in the last week; it is almost always the thing that should not come.

Last, leave a gap. A bag that is full at departure is overfull on the way home. Pack to about 80 per cent, buy the thing in the market you swore you would not, and know that the bag still closes.