If your carry-on is too large – or too overstuffed – you might get stopped at the gate before boarding. Sometimes flight attendants will have to tag your bag and send it off to be stowed with checked luggage.

If your carry-on bag is found to be over the weight limit in 2026—a limit that is increasingly strictly enforced—the most common outcome is a mandatory gate-check and a premium fee. Many airlines, particularly European and Asian carriers, now use "automated sizers" that weigh and measure your bag simultaneously during the boarding process. If your bag exceeds the standard 7kg to 10kg limit, you will be required to check it into the cargo hold. Because this happens at the gate rather than the check-in counter, the fee is often higher (ranging from $50 to $100). If the flight is very full, a heavy bag might also be rejected due to "weight and balance" safety calculations for the aircraft. To avoid this, travelers in 2026 often wear their heaviest clothing or use "wearable luggage" (jackets with many pockets) to move weight out of the bag before reaching the scales, as personal items and clothing usually aren't weighed.