REI Co-op Ruckpack 18 vs. Millican Smith 25L

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

REI Co-op Ruckpack 18

Front facing view of the REI Co-op Ruckpack 18
Capacity18 L
Weight0.7 kg
Dimensions44×26×18 cm
Airline fit96%
Price$65

Feature by feature

REI Co-op Ruckpack 18FeatureMillican Smith 25L
Storage
Compression N
None Expanded Capacity None
0 Opening 2
side Passport side
N Passthrough N
Carry
Backpack Y
removable Hip Belt removable
removable Sternum Strap removable
Inside
15in Laptop 15in
2 Main Compartments 4
Y Organizer Y
Outside
× Hard Shell ×
N Rain-fly N
Water Bottle Holder 2, side
Y Water Resistant Y
Material
210-denier nylon ripstopWeatherproof Bionic Canvas

Millican Smith 25L

Front facing view of the Millican Smith 25L
Capacity25 L
Weight1.1 kg
Dimensions52×28×18 cm
Airline fit89%
Price$145

Key differences between the REI Co-op Ruckpack 18 and Millican Smith 25L

Both have: passport pocket, hip belt, 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. 168 accept both. 13 accept only the REI Co-op Ruckpack 18, and 0 accept only the Millican Smith 25L.

Only the REI Co-op Ruckpack 18 fits

Air Niugini, Air Tahiti, American Eagle, Belavia, easyJet, Etihad Airways, Gulf Air, Oman Air, Qatar Airways, Ravn Alaska, Regional Express, Royal Jordanian, Virgin Australia.

REI Co-op Ruckpack 18 vs. Millican Smith 25L: which should you pack?

The Millican Smith 25L carries 7L more than the REI Co-op Ruckpack 18 (18L vs. 25L), while the REI Co-op Ruckpack 18 is the lighter pack at 0.7kg (vs. 1.1kg). For carry-on flexibility, the REI Co-op Ruckpack 18 fits 96% of the airlines we track — the higher of the two. If you prioritise packing volume, choose the Millican Smith 25L; if you want to travel lighter, the REI Co-op Ruckpack 18 is the better call.