Maximise Carry-On Space: 12 Tactics That Actually Work
Maximising carry-on space is a series of small wins that compound. Twelve tactics below, ranked by impact, with the rough percentage of saved space each one delivers. Tested on a 40L wheeled carry-on with a 5-4-3-2-1 packing load. Sits inside our how to pack a carry-on guide.
The 12 tactics ranked by impact
Total possible saving if you stacked every tactic: around 45-50 percent more effective volume vs a naive pack. Most travellers find 25-30 percent is the realistic stack.
1. Use compression packing cubes (~30% on soft loads)
The biggest single tactic. Compression cubes free roughly 30 percent more volume on soft-fabric loads (t-shirts, jumpers, fleece). On dense loads (jeans, books) the gain is around 10 percent because there's less trapped air to remove. The Cubey Signature Compression Packing Cube Set ($99) is built for this; full category breakdown in our compression cubes guide.
2. Wear bulkiest items on the plane (~20% of bag weight off the cap)
Heaviest shoes, biggest jumper, jacket, and trousers go on your body. That's 1.5-2kg of stuff that doesn't count against the 7kg scale and doesn't take cube space. The single highest-leverage tactic outside compression cubes.
3. Roll, don't fold (~15% volume reduction inside the cube)
Rolling fills the cube with fewer air gaps than folding. Combined with cubes, the wins compound. Detail in our roll vs cubes guide.
4. Stuff your shoes (~1 litre of recovered volume)
Socks and underwear go inside the shoes you're packing. Two pairs of shoes have roughly 1 litre of internal volume that's otherwise wasted. Stuffed shoes also retain their shape better in transit.
5. Use a collapsible water bottle (~500ml saved)
A collapsible silicone bottle (Decathlon, Hydrapak, Kathmandu, around $25) packs flat into a cube. Saves the 500ml volume of a rigid bottle. Refill past security.
6. Decant toiletries to 60-100ml (~70% volume reduction on liquids)
Standard shampoo and conditioner bottles are 250-500ml. Decanted into 60-100ml silicone bottles, the volume of your liquids section drops by roughly two-thirds. Plus you stay compliant with the 100ml carry-on rule.
7. Use the personal item allowance (~4-5kg of separate capacity)
Most AU airlines allow a carry-on (7kg) plus a personal item (no enforced weight on most lines, just size). Use the personal item for laptop, book, water bottle, headphones, snacks. Frees real space in the carry-on for clothes and toiletries.
8. Buy toiletries at destination (~100-200g per item)
Shampoo, conditioner, body wash, sunscreen, moisturiser bought at destination saves the weight and volume of every bottle. Useful when destinations have cheap pharmacy options (Bali, Bangkok, anywhere in Asia and most of Europe).
9. Switch dense fabrics for lighter equivalents (~200-400g saved)
A merino t-shirt weighs less than a cotton one and dries faster after a sink wash. A technical fleece weighs less than a cotton jumper. Lightweight chinos weigh less than jeans. Where the trip allows, swap dense for light.
10. Skip the "just in case" outfit (~300-500g)
The fancy dress for a maybe-event, the second jacket "in case it gets colder", the third pair of shoes "for fancy dinners". Drop them unless confirmed.
11. Solid alternatives where they exist (~100-200ml of liquid allowance freed)
Shampoo bars (Lush, Ethique, Beauty Kubes) replace liquid shampoo and bypass the 100ml rule. Solid deodorant stick replaces aerosol. Solid sunscreen sticks exist for face. Each solid switch frees space in your liquids section.
12. Repack mid-trip (~10% recovered volume)
On day 5 of a trip, dirty clothes consolidate into the laundry bag while clean clothes get re-folded into fresh cubes. You'll find you can repack tighter than you packed originally because some items have shrunk through wear.
How the tactics stack
Most of these are additive. A traveller who uses compression cubes + wears bulkiest on plane + decants toiletries + stuffs shoes + uses the personal item allowance gets roughly 40-50 percent more effective capacity than someone who does none of them. That turns a 40L bag into a functionally 55-60L bag, at no extra cost in weight or money.
The diminishing-returns point: stack the first six tactics and you'll cover 80 percent of the gain. Tactics 7-12 are useful but marginal. If you do nothing else, do compression cubes + wear bulkiest on plane + roll your clothes.
What doesn't work (despite the internet's enthusiasm)
A few tactics get recommended widely but don't deliver in real conditions.
Vacuum-sealed bags. They lose seal on day three of any humid trip. Compression cubes do the same compression job with no seal to fail. Tested in our roll vs cubes guide.
Wearing 10 layers on the plane. Two layers (jumper + jacket) is genuinely useful. More than that makes airport security awkward (you have to take everything off at scanning) and you sweat through the layers in the terminal anyway.
Sucking air out of cubes manually before sealing. Tried in TikTok videos; doesn't move the needle vs compression cubes, which compress mechanically.
Wearable luggage vests with 20 pockets. Bizarre. Sometimes effective for tech-heavy travellers. Mostly silly.
Trip-length-specific space-saving moves
Weekend (2-3 days): compression cubes don't save much because you're not packing much. The biggest win is wearing bulkiest items on the plane and using the personal item for toiletries.
One week: compression + wear-on-plane + decanted toiletries = full carry-on with room.
Two weeks: compression + wear-on-plane + decanted toiletries + laundry mid-trip = full carry-on with room. The laundry move multiplies wardrobe rather than packing more.
10+ days carry-on only: every tactic stacked. Compression maxed. Laundry every 4-5 days. Buy bulky items at destination. The Cubey Signature Set works at this length, just barely.
FAQ
How do I maximise carry-on space?
Twelve tactics stack: compression packing cubes (~30 percent on soft loads), wear bulkiest items on the plane (~20 percent of weight off the cap), roll clothes inside cubes, stuff your shoes with socks, use a collapsible water bottle, decant toiletries to 60-100ml, use the personal item allowance, buy toiletries at destination, switch dense fabrics for lighter equivalents, skip just-in-case outfits, use solid toiletry alternatives, and repack mid-trip.
Do compression cubes really save 30% space?
On soft-fabric loads (t-shirts, jumpers, fleece), yes. We measured 37 percent vertical-height reduction on a six-outfit soft-only load in our compression cubes test. On dense loads (jeans, books) the gain is closer to 10 percent because there's less trapped air.
How do I pack shoes in a carry-on without wasting space?
One pair worn on the plane, one pair in a shoe bag at the bottom of the suitcase. Stuff socks and underwear inside the packed shoes (roughly 1 litre of recovered internal volume across two pairs).
How do I fit a laptop in a carry-on?
Most 40L wheeled carry-ons have a dedicated laptop sleeve in the back panel. If your bag doesn't, put the laptop in your personal item (laptop bag, small backpack). A laptop in the main compartment risks damage from compression and shifts the bag's centre of gravity.
Are vacuum-sealed bags worth it for travel?
No. They lose seal in humid conditions and replicate what compression cubes do without the failure mode. Skip them.
Does wearing your bulkiest items on the plane really make a difference?
Yes. A jacket, jumper, jeans, and heaviest shoes worn on the plane move 1.5-2kg off the bag weight (20-30 percent of the 7kg carry-on cap). And free meaningful volume because those items don't need cube space.
What Cubey makes for this
The compression cube case specifically: Signature Compression Packing Cube Set ($99). For the full system at 25 percent off: Wheels Up Bundle ($148).
The practical takeaway
Stack compression cubes + wear bulkiest on plane + decant toiletries. Three tactics cover 80 percent of the possible space gain. Everything else is marginal.
