Monos vs Béis: which carry-on is for you?

Monos and Béis are both design-led, direct-to-consumer carry-ons, and most comparisons stop at taste: Monos is the quiet, minimalist one and Béis is the colorful, feature-loaded one. That is true as far as it goes. What almost nobody says is that these two bags are not the same size. Monos publishes its Carry-On at exactly 22 x 14 x 9 in. Béis publishes The Carry-On Roller at 22.83 x 15.70 x 10 in (58 x 40 x 25.4 cm) — over the US carry-on convention on all three dimensions. That is the fact that should lead this comparison, and it explains most of the others.

Neither is sold on Amazon, so both buy links below go direct to the brands and we earn nothing on either — we would rather point you at the right bag. For comparable carry-ons you can buy on Amazon today with live prices, our best carry-on luggage picks cover the field.

Spec by spec

Figures as published by each brand at the time of writing. Béis's own product page does not claim airline approval; it publishes a sizing chart and advises confirming with your airline, which is a fair thing for them to say and a fair thing for you to act on.

The size difference is the whole story

Nine extra liters sounds like a straightforward win for Béis, and if you never meet a sizer it effectively is. But the capacity does not come from cleverer engineering; it comes from the bag being bigger. At 22.83 in tall the Béis is nearly an inch over the 22 in height standard, at 15.70 in it is 1.7 in over the 14 in width, and at 10 in deep it is a full inch over the 9 in depth — before you use the 2 in expansion, which takes it to a published 61 L.

What that means in practice depends entirely on where you fly. On US domestic mainline flights, almost nothing: gate agents rarely sizer-check a bag that reads as normal luggage, and the bins take it. On a European low-cost carrier with a drop-in template, on a regional jet, or on any carrier that actually measures, an over-size bag is a gate-check fee and a bag in the hold. Our carry-on size by airline table has the published limits, and how to measure luggage explains why the number on the box is often not the number the sizer sees.

Buyer-first version: if you want a Béis and you want it to clear a sizer, look at the Small Carry-On Roller rather than the standard one. Same design language, smaller footprint. If you want a bag that publishes at exactly the US standard, that is Monos.

The weight indicator tells you what Béis expects

Béis builds a weight indicator into the carry handle that changes color when the packed bag hits 50 lb. It is a genuinely clever touch and it is also a tell: 50 lb is the standard free checked-bag allowance, not a cabin-bag number. No airline lets you bring 50 lb into the cabin. The feature is designed for a bag that gets checked — which is consistent with the published dimensions and, to be fair to Béis, consistent with how a lot of people actually use a 21-inch case. Our checked bag size and weight limits guide covers where that 50 lb line comes from.

The other Béis extras are more straightforwardly useful: a hidden pocket for a tracker, a bag hook rated to 30 lb, gap-free tapered zippers with a TSA-accepted lock, and compression straps. Monos answers with a felt-lined interior, vegan-leather trim and laundry and shoe bags included in the box. Both sets are real; they just serve different buyers.

Weight, and what it costs you

Monos publishes 7.01 lb empty; Béis publishes 7.81 lb (3.55 kg). That is 0.8 lb, and like most weight differences in this category it is invisible domestically and expensive internationally. On a 7 kg cabin cap the Béis has consumed just over half your allowance before you pack, against about 45% for the Monos. Neither is a bag for weight-capped routes — see our lightweight carry-on picks if that is your flying — but if you are choosing between these two and you fly international economy, the lighter bag is the Monos and it is not close enough to ignore.

Who should buy which

Buy Monos if you want a carry-on that publishes at exactly 22 x 14 x 9, weighs the least of the two, and reads as understated. It is the safer bag for anyone who flies internationally or on regional aircraft, and the more premium-feeling one inside.

Buy Béis if you want the color, the organization and the clever hardware, you mostly fly US domestic mainline routes, and you are relaxed about a bag that is over the published standard — or you are willing to buy the Small Carry-On Roller instead. It holds meaningfully more, and for a lot of travelers that is the trade they would take knowingly.

Buy neither if you want the best bag per dollar. Both are premium-priced direct-to-consumer purchases, and an Amazon-available polycarbonate spinner delivers most of the function for less — the argument our best hardside luggage ranking makes in full.

Direct-to-brand links — neither is on Amazon and we do not earn a commission on these.