+Fares are subject to additional charges, including, without limitation: the September 11th Security Fee of $2.50 per enplanement at a U.S. airport up to a maximum of two enplanements per one-way trip; Passenger Facility Charges of up to $18, depending on itinerary; and Federal Segment Fees of $3.70 per segment. A segment is defined as a takeoff and a landing. Fares to/from Alaska or Hawaii do not include Travel Facilities Tax of up to $8.10 each way. Fares to/from Puerto Rico and the U.S. Virgin Islands do not include U.S. Departure Tax of $16.10 each way. Fares for international travel do not include up to $250 in government-imposed fees per roundtrip, a portion of which may be collected by the foreign government, depending on routing and destination.