Carry-on bags to be stored in the overhead compartments may not be larger than 24 inches long, 17 inches wide and 10 inches high. These size requirements include the wheels and handles that may stick out from the body of the luggage. Smaller personal items are to be stowed underneath the seat in front of the passenger.
Some packed items are acceptable for checked baggage but are not allowed in carry-ons. These include, but are not limited to, personal air purifiers, sharp objects, weapons and liquids stored in large-volume containers. According to TSA rules, liquids can only be stored in carry-on baggage as long as they are placed in a clear, plastic zipper bag and are less than 3.4 ounces. Additional restrictions may come about as a result of changes in TSA policy.
Overhead space is limited, so late-arriving bags on fully booked flights may not be able to be placed in a compartment. As of 2010, Alaska Airlines checked these bags for free at the gate to be picked up on the ramp at the end of the flight. Carry-on luggage that does not meet requirements or exceeds limits according to Alaska Airlines are subject to a checked bag fee.
