United Airlines charges $25 for the first checked bag weighing up to 50 pounds and $35 for the second bag (as of November 2010). Each passenger is allowed one piece of carry-on luggage, not to exceed 45 linear inches and a small personal item, such as a small backpack, purse or briefcase. For most international travel, at least one free checked bag is permitted. Details for individual countries can be found on the United Airlines website.
United Airlines recommends you arrive at least 60 minutes before a domestic flight if you are not checking baggage and at least 90 minutes before the flight if you are checking baggage. For international flights, you should arrive at least two hours before the scheduled departure time. You may need more time if you are traveling during the holiday rush or another busy travel time. Your seat assignment may be canceled if you do not receive your boarding pass 30 minutes before departure or are not at the gate 20 minutes before departure.
Passengers aged 18 and older must present a federal-or state-issued ID such as a driver's license, passport or military ID. Other acceptable forms of identification are listed on the United Airlines website. A passport is required for all international travel. You may also need a visa or other documents depending upon the laws of the country you are visiting.
