In 2026, the frequency of carry-on size checks has increased significantly as the industry moves toward a universal standard of 22 x 14 x 9 inches. Budget airlines like Frontier, Spirit, and Ryanair check almost every passenger's bag using metal sizers at the gate, as baggage fees are a primary revenue source. Major legacy carriers like Delta and United have also stepped up enforcement due to "carry-on crunch," where overhead bin space runs out before boarding is complete. Interestingly, some airlines like American Airlines have begun removing traditional sizers to speed up boarding, but this has actually increased "gate-agent discretion," leading to more frequent and sometimes inconsistent checks. As of early 2026, many airports have also integrated sensors at security or kiosks that can "eye" a bag's volume. To avoid being forced to gate-check and pay unexpected fees, travelers are now advised to measure their luggage including wheels and handles, as even a protruding bumper can now cause a bag to fail a check in front of the entire boarding group.