Bellroy Transit Backpack vs. Thule Aion 40L

Two carry-on travel backpacks, compared spec for spec.

Bellroy Transit Backpack

Front facing view of the Bellroy Transit Backpack
Capacity28 L
Weight1.1 kg
Dimensions53×36×19 cm
Airline fit81%
Price$250

Feature by feature

Bellroy Transit BackpackFeatureThule Aion 40L
Storage
N Compression N
None Expanded Capacity None
1 Opening 1
top Passport top
N Passthrough Y
Carry
Y Backpack Y
N Hip Belt optional
Y Sternum Strap Y
Inside
16in Laptop 16in
4 Main Compartments 4
Y Organizer Y
Outside
× Hard Shell ×
N Rain-fly N
2, side Water Bottle Holder 1, side
Y Water Resistant Y
Material
Baida Nylon

Thule Aion 40L

Front facing view of the Thule Aion 40L
Capacity40 L
Weight1.5 kg
Dimensions52×33×23 cm
Airline fit70%
Price$200

Key differences between the Bellroy Transit Backpack and Thule Aion 40L

Both have: passport pocket, backpack straps, sternum strap, laptop sleeve, built-in organizer, water resistant.

Which airlines take each bag as a carry-on

We checked both bags against the carry-on size limits of 189 airlines. 120 accept both. 33 accept only the Bellroy Transit Backpack, and 12 accept only the Thule Aion 40L.

Only the Bellroy Transit Backpack fits

Air Baltic, Air China, Air Malta, Air Serbia, Air Seychelles, Asiana Airlines, ATA Airlines, Blue Air, Bulgaria Air, China Eastern, Emirates Airlines, Enter Air, Icelandair, Juneyao Airlines, Liat Airlines, Luxair, Meridiana Fly, Nordwind Airlines, Pakistan International, Royal Brunei Airlines, Ryanair, S7, Shandong Airlines, Shenzhen Airlines, Sun Express, TAP Air Portugal, TAROM, Tianjin Airlines (A320 & E190), TUI, Ukraine International, VIM Airlines (Closed), Volotea, Xiamen.

Only the Thule Aion 40L fits

Aerolineas Argentinas, Air France, Air India, Air Mauritius, Boliviana de Aviacion, Cayman Airways, Indigo, Jet Airways, Kenya Airways, KLM, LATAM , Sky Airlines.

Bellroy Transit Backpack vs. Thule Aion 40L: which should you pack?

The Thule Aion 40L carries 12L more than the Bellroy Transit Backpack (28L vs. 40L), while the Bellroy Transit Backpack is the lighter pack at 1.1kg (vs. 1.5kg). For carry-on flexibility, the Bellroy Transit Backpack fits 81% of the airlines we track — the higher of the two. If you prioritise packing volume, choose the Thule Aion 40L; if you want to travel lighter, the Bellroy Transit Backpack is the better call.