Thule Subterra 34L vs. Thule Aion 40L
Two carry-on travel backpacks, compared spec for spec.
Thule Subterra 34L
| Capacity | 34 L |
| Weight | 1.2 kg |
| Dimensions | 52×31×23 cm |
| Airline fit | 70% |
| Price | $180 |
Feature by feature
| Thule Subterra 34L | Feature | Thule Aion 40L |
|---|---|---|
| Storage | ||
| N | Compression | N |
| None | Expanded Capacity | None |
| 2 | Opening | 1 |
| side | Passport | top |
| Y | Passthrough | Y |
| Carry | ||
| Y | Backpack | Y |
| N | Hip Belt | optional |
| Y | Sternum Strap | Y |
| Inside | ||
| 15in | Laptop | 16in |
| 4 | Main Compartments | 4 |
| Y | Organizer | Y |
| Outside | ||
| × | Hard Shell | × |
| N | Rain-fly | N |
| 1, side | Water Bottle Holder | 1, side |
| Y | Water Resistant | Y |
| Material | |
| 800D nylon | |
Key differences between the Thule Subterra 34L and Thule Aion 40L
- Opening: Rolltop on the Thule Subterra 34L; Clamshell on the Thule Aion 40L.
- Passport pocket: Side on the Thule Subterra 34L; Top on the Thule Aion 40L.
- Hip belt: No on the Thule Subterra 34L; Optional on the Thule Aion 40L.
- Laptop sleeve: 15in on the Thule Subterra 34L; 16in on the Thule Aion 40L.
Both have: luggage passthrough, backpack straps, sternum strap, built-in organizer, water bottle pockets, water resistant.
Which airlines take each bag as a carry-on
We checked both bags against the carry-on size limits of 189 airlines. 132 accept both. Every airline that takes one takes the other.
Thule Subterra 34L vs. Thule Aion 40L: which should you pack?
The Thule Aion 40L carries 6L more than the Thule Subterra 34L (34L vs. 40L), while the Thule Subterra 34L is the lighter pack at 1.2kg (vs. 1.5kg). For carry-on flexibility, the Thule Subterra 34L fits 70% 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 Thule Subterra 34L is the better call.