In 2026, American Airlines has significantly tightened its enforcement of the 22 x 14 x 9 inch carry-on rule. While they have moved away from traditional metal "sizers" in some terminals, they have replaced them with AI-powered camera scanners at the gate that can instantly flag bags exceeding these dimensions (including wheels and handles). If your bag is flagged by the system, gate agents have very little discretion to let it slide, and you will likely be charged a gate-check fee (ranging from $35 to $65). Soft-sided bags that "bulge" are particularly scrutinized in 2026. However, the strictness can vary based on the aircraft; regional Embraer jets have much smaller overhead bins, leading to mandatory "valet" checking of almost all roller bags, regardless of size. To avoid issues in 2026, it is vital to measure your bag when it is fully packed, as an "expanded" zipper often pushes a compliant bag over the limit. Basic Economy passengers face the highest scrutiny, as their fare specifically limits them to one personal item that must fit under the seat.