For 2026, the standard carry-on size for major U.S. airlines like American, Delta, and United remains 22 x 14 x 9 inches (56 x 36 x 23 cm), including all wheels and handles. Southwest Airlines is a notable exception, allowing slightly larger bags up to 24 x 16 x 10 inches. Budget carriers like Spirit and Frontier are significantly stricter, often restricting "free" hand luggage to a Personal Item that must fit under the seat, typically around 18 x 14 x 8 inches. For international travel, many European and Asian carriers enforce a weight limit ranging from 15 to 22 pounds (7–10 kg), which is rarely checked in the U.S. but is a point of strict enforcement abroad. Travelers are advised to use a "bag sizer" at the gate, as modern 2026 security protocols have reduced the "leeway" for soft-sided bags; if it doesn't fit in the metal frame, it must be checked for a fee that often exceeds $65.