PRO TIP: If you know you’re going to need a carry-on or a checked bag, buy it right when you book your flight to save major moola. Personal item (e.g., purse, small backpack, etc.): Dimensions must not exceed 16 x 14 x 12 inches (40 x 35 x 30 cm) including handles and wheels. For travel after 3/31/2016, dimensions must not exceed 17 x 13 x 8 inches (43 x 33 x 20 cm) including handles and wheels.