Southwest Airlines

Southwest Airlines operates an open-seating policy, though passengers are boarded in three tiers (those with boarding cards "A" first, followed by "B", followed by "C"), so it pays to check-in early. EarlyBird check-in passengers will receive a reserved boarding position 36 hours prior to boarding. The fee for this is $10 per flight.

Reservations purchased online may be changed online (via the Change Air Reservation page). To change a reservation that was not made online, call 1-800-I-FLY-SWA. Southwest does not charge a fee to change a booking; passengers pay just the difference in fares.

Infants under two years of age can travel for free, if travelling on an adult's lap. Infant and child fares are not available to purchase online. Passengers are requested to call 1-800-I-FLY-SWA for details.

Available for those 65+. Prices vary from city to city. Senior airfares are fully refundable and exchangeable. Fares can be booked online or via the reservations number.

Pets (cats and dogs) may travel in the cabin with their owners (under the owner's seat). The fee is $75 (approx £46) each way.

Musical instruments can be carried on if they meet the size requirements for carry-on items. You can also purchase a seat for a large or fragile instrument at a child's fare rate, but an instrument cannot be carried in place of a free companion under any fare promotion.

Peanuts and pretzels are served free of charge, as are soft drinks. Beer, wine or cocktails are available for purchase. Satellite-enabled WiFi internet access is available onboard several flights. The fee is about $5.

Rapid Rewards allows you to earn miles when you fly Southwest. Rapid Rewards are based on the number of flights you make, rather than the miles you travel and redeemed with a number of partners, including Alamo, Budget, Hertz and Hilton.

See photographs of meals and read reviews at AirlineMeals.net.

Spirit, Southwest's in-flight magazine is available on every flight and can be read online.

Southwest Airlines has a partnership with discount Mexican airline Volaris.

Forty years old in 2011, Southwest Airlines is the low-cost pioneer, model for many a low-cost carrier including Ryanair. In May, Southwest Airlines purchased AirTran Airways. Both airlines will continue to operate as separate businesses until they receive a Single Operating Certificate from the Federal Aviation Administration. The conversion of AirTran's aircraft to Southwest livery will start in 2012. The new, merged, airline will carry 100 million passengers each year.

Southwest flies to 72 cities in 37 states and offers excellent customer service. Passengers receive a free baggage allowance, there are no change fees (just the difference in fares to pay) and satellite-enabled WiFi internet access is available onboard.