How to Master One-Bag Travel: 8 Items I Pack and 8 I Leave Behind

I’m a frequent traveller, and I have no room in my life or my backpack for single-use clutter or ‘just-in-case’ panic packing. For me, streamlining the things I travel with isn’t just about weight; it’s about freedom.

If you scroll through r/onebag, you’ll see a lot of 40L to 45L carry-on setups pushing the absolute limits of transatlantic overhead bins – which, let’s be honest, is often two-bag travel in disguise. That’s fine for some, but it’s not how I travel. My baseline is strict budget-airline limits: a single under-seat bag that fits in the infamous 40x30x20cm Ryanair sizer. Every single item in this list has to earn its spot in that footprint.

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The 8 Things That Make Packing Light Easy

Here are 8 essentials that make my style of one-bag travel effortless, and 8 unnecessary items I can happily do without.

1. Under 30L Backpack

Limiting your main bag to under 30 L sets a strict physical ceiling. A simple layout with minimal built-in organisation beats a complex, heavy bag. It keeps the weight down, works as an under-seat personal item on strict-budget airlines, and leaves room to drop in modular packing cubes and pouches with wiggle room.

Pick a durable bag with strong zips that won’t let you down. Make sure it’s built for comfort, not for an over-engineered tick list. Pick a colour like black, grey or navy and avoid shouty logos if you don’t want to stand out.

➡️My Pick: CabinZero Military 28L Backpack

2. 5L Crossbody Sling

A medium sling keeps essentials close at hand while exploring without a backpack. When moving between destinations, it slides right into the top of the main pack. 5L is the sweet spot: room for a water bottle and valuables without forcing a game of Tetris to zip it up.

On the outside, my bag looks similar to the viral Uniqlo crescent bag. But delve deeper, and it’s a definite upgrade. Fully weather-resistant, a light colour lining to make it easier to see everything inside, an anti-theft toggle to secure the zip, internal pockets and two external pockets, one with RFID. Wear it how you like. Either tight to your body, as a sling or to one side. It’s not loud or original, but that’s the point, it will take you anywhere,

➡️My Pick: CabinZero 5L Moon Bag

3. Ultralight Packing Cubes

Cubes act as a mobile wardrobe, keeping clothes organised and compressed. Choosing cubes designed to match your bag’s internal dimensions eliminates dead space. Look for ripstop nylon, strong three-sided zips, and optional compression and learn to roll your clothes in a way Marie Kondo would be proud of. I use a large compression cube for my tops, bottoms and any dresses and a medium one for underwear, sleepwear, and accessories

➡️My pick: CabinZero Ultralight Compression Cubes (Large & Medium)

4. Packable Bags

Instead of carrying one heavy daypack, carry paper-thin but incredibly strong, packable options to adapt on the fly. They weigh under 30g each, take up zero space, and adapt to changing needs. I usually carry 3!

• 19L Packable Sling: Extra capacity for days when 5L isn’t enough. Adding plenty of room for those layers you might need to take on and off, for storing a picnic or for a day at the beach, while shopping, or for anything else.
• 16L Packable Daypack: A neat little daypack for day hikes when you need it, but a shoe bag for your dirty shoes when you don’t.
• Packable Tote: For separating and transporting your dirty clothes to the laundry facilities. And of course, for anything else, you might need it.

➡️My pick: Nanobags

5. Multi-Weather Tech Jacket

For all but the coldest or wettest weather, a single high-performance jacket replaces bulky hoodies, heavy coats, and rain shells. Pick a synthetic ultralight insulated jacket. Mine has a hood, performs well in the rain, and keeps my head warm and dry, especially when paired with an ultralight umbrella. With a matte finish in black or muted colourways, it’s low-profile enough for the city without looking too ‘outdoorsy. Worn slightly oversized, so I can wear a warmer layer underneath or a rain shell on top for more extreme conditions.

➡️ My pick: Finisterre Firecrest Hooded Jacket (available in both men’s and women’s sizes)

6. Ultra-Supportive Packable Shoes

Shoes are usually the hardest item to optimise. Unless your feet are trained for barefoot styles, avoid floppy, flat soles that offer zero support. Instead, choose an ultralight trainer (mine are around 300g per pair – UK Size 6.5 / EU 40). Pick shoes with a cushioned footbed, firm midsole, arch support, heel grip, non-slip soles and squashable uppers. These will take you to most places and work with most outfits. Suitable for the gym and in the water as well. If you need another pair of shoes, like a sandal, boot, or dress shoe, you’ll still have room.

➡️My pick: Clarks Cloudstepper Solevena Tie (available in both men’s and women’s sizes)

7. Multi-Port GaN Wall Plug with Swappable Ends

Ditch single-purpose chargers and bulky travel adapters. A single 65W GaN plug with interchangeable global snap-on heads powers a laptop, phone, and power bank simultaneously via USB-C cables, and if it comes with USA/UK/Euro plug ends, it will work in over 150 countries. And if that’s not enough countries, pick up an extra adapter locally.

IF you’re still travelling with your proprietary laptop cable and struggling with international adapters which fall out of the wall when you attach another thing to them, making the switch will make a big difference to you.

➡️My pick: UGREEN 65W GaN Charger (International Version)

8. Concentrated Laundry Sheets

Laundry is non-negotiable when packing light. Liquid-free laundry sheets weigh virtually nothing, bypass airport liquid restrictions, and work equally well in a laundromat machine or a hotel sink.

And if you think you’ll run out of space to do your washing or hang it up, bring a small scrubba bag and a portable clothesline. If I’m washing just for myself, I don’t need this.

➡️My pick: Dr Beckmann Laundry Sheet

And 8 Things I Don’t Bring

1. Full-Sized Hair Tools

I’d love big waves, but my hair is straight. Embracing my natural texture, maintaining its condition when I’m away with quality hair products, and keeping it trimmed in a low-maintenance style saves a lot of bag space. It also eliminates the need for voltage converters entirely.

2. Bulky Travel Adapters

Heavy, blocky all-in-one adapters easily drop out of wall sockets. With everything charging via USB-C, a single slim 65W GaN plug with modular snap-on heads does the work of multiple separate chargers and an international adapter.

3. “Needy Gadgets”

If a device requires its own proprietary cable and daily charging, it doesn’t make the cut. Gear should work for you, not give you chore lists on holiday. Yes, this is a direct swipe at many smartwatches. But they are not all the same. I have a Withings ScanWatch 2, with plenty of smart features and a beautiful analogue display. It lasts 30-35 days between charges.

4. Decanted Liquids & Lotions

Decanting creams into tiny plastic pots is time-consuming, messy, prone to leaks, and easy to forget to label. I don’t like the cost or the single-use plastic element of travel minis. I opt for solid multi-use bars, dry oil and tins. Zero-waste, take up little space, easily comply with liquid allowances and last at least a month.

5. A Third Pair of Shoes

Shoes take up more volume than almost anything else in a pack. Your favourite pair on your feet and one ultra-lightweight pair in the bag are all you need for most itineraries, formal, casual, or active. Just choose carefully.

6. Bulky Tech and Toiletry Organisers

Dedicated organisers are often heavy, bulky, and obsolete the moment your gear changes. Soft pouches or lightweight backpack pockets adapt to your tech far better than rigid cases, and a simple pouch for your toiletries is sufficient, provided you don’t have too many items.

7. Dedicated Travel Liquids (Shampoo, Wash, Detergent).

Carrying separate bottles for body wash, shampoo, and laundry detergent adds needless weight. Multi-purpose solid bars and concentrated laundry sheets handle daily hygiene and sink washing in one go.

8. “Just-In-Case” Packing & Imaginary Outfits

Packing for unlikely “what-ifs” or an idealised holiday wardrobe leads to overpacking. Stick to your actual daily comfort zone: if a problem arises, a quick trip to a local shop or a bit of lateral thinking will solve it. Don’t let perfect be the enemy of the good.

Minimalist packing isn’t about suffering through a trip with the bare minimum. It’s about removing the friction so you can focus on where you are. By removing the excess, swapping for adaptable essentials, and quieting the ‘what-if’ scenarios, you free up space, time, and peace of mind.

What’s the one item holding your packing list back?