Most carry-on mistakes happen before the trip: a bag that is a little too wide, too heavy empty, or covered by a warranty that excludes the way suitcases usually break. This checklist draws on three outside sources, which we credit below, and applies it to a real example.
1. Decide between hardside and softside
SwissGear summarizes the trade-off in one line: hardside resists compression better and softside resists abrasion better. Hardside shells, usually polycarbonate, ABS or polypropylene, handle crushing and impacts well but show scuffs and scratches, and they wipe clean. Softside fabric gives a little, often adds an expansion zipper and usually has exterior pockets. Travelpro, which mostly sells softside bags, adds that most hardsides open into two roughly equal halves, which is awkward for bulky items, and that a thick rigid shell can crack when dropped. Both sources say build quality matters more than the shell type.
2. Compare empty weight and real dimensions
Weight on the tag is only part of the story. SwissGear suggests comparing empty weight, wheels, handle comfort and balance, and notes that modern hardsides have closed much of the old weight gap. For size, use the numbers a reviewer measured rather than the label. Pack Hacker measured the Level8 Voyageur 20 in carry-on at 21.3 by 15.1 by 9.8 inches and 8.1 lb (3.7 kg), and rated its carry-on compliance at 17%, based on 25 of 146 airlines, as a guideline and not a guarantee.
3. Check wheels, handle, zippers and corners
SwissGear gives a short hands-on checklist: smooth, sturdy wheels, a handle that feels stable when extended, zippers that move without snagging, reinforced corners and a bag that stands upright when packed. In the Level8 test, Pack Hacker praised the wheels, a full-width handle and a shell that resisted scratches, but found that most backpack pass-throughs do not fit over the wide handle and that the zipper can be hard to close when the sides are not aligned, which is the kind of trade-off a spec sheet will not show.
4. Check your airline's limits, including weight
Limits vary a lot. Level8's airline guide lists, for example, Delta at 22 by 14 by 9 inches with no weight limit, Southwest at 24 by 16 by 10 inches, Qatar at 20 by 15 by 10 inches and 15 lb (7 kg), and Cebu Pacific at 22 by 14 by 8 inches and 11 lb (5 kg). The same page warns that the figures change and are based on economy class, and advises checking each airline's own site before you fly. A bag can be slightly over on one dimension and still be accepted on a given day, so treat that as luck and not as a plan.
5. Read what the warranty excludes
A long warranty is only useful if it covers the damage you are likely to get. Look for the term (“lifetime” is not always defined), whether airline transport damage is covered, who pays shipping for a repair, and what proof you need. Brand warranties are claims to be read closely, not guarantees of how a claim will go. If you may want to return the bag, also check who pays return postage and how long refunds take.
An example: checking a bag against the list
In our Level8 Cases review we applied these questions to the brand's luggage. The warranty covers manufacturing defects in the shell, wheels, handles and zippers, but excludes airline transport damage, misuse and normal wear and tear and does not define “lifetime”. Returns are accepted within 30 days, with the customer paying return shipping. That is exactly the kind of fine print worth settling before you pay.
A note on the sources
Travelpro and SwissGear are luggage makers, and their guides favor their own products, so we used them for general trade-offs and not for product claims. Pack Hacker is a gear publication whose test covers one model. Level8's airline guide is a brand page and the limits it lists may have changed. We wrote this article in our own words and did not copy text. Some links to brands on this site are affiliate links; see our affiliate disclosure.