The price policy of the low cost carriers is usually very dynamic, with discounts and tickets in promotion. Like other carriers, even if the advertised price may be very low, it often does not include charges & taxes. With some airlines, some flights are advertised as free (plus applicable taxes, fees and charges). Depending on the airline, perhaps as many (or as few) as ten percent of the seats on any flight are offered at the lowest price, and are the first to sell. The prices steadily rise thereafter to a point where they can be comparable or more expensive than a flight on a full-service carrier.
Most airlines charge additional taxes and fees on their tickets. Some Low cost airlines have been known to charge fees for the seemingly ridiculous, such as levying a credit card charge where credit card is the only payment method accepted. Many consumers and governments consider this to be fraudulent, but some still allow this and similar practices.
Traditional perceptions of the "Low cost airlines" as a stripped-down, no-frills airline, as seen on Southwest Airlines, have been changing as new entrants to the market adapt the business model in new ways. AirTran Airways and Spirit Airlines offer a premium cabin while Frontier and JetBlue offer live in-flight television, sometimes for an extra fee. AirTran has XM Satellite Radio available at every seat. Frontier, JetBlue, and AirTran all use assigned seating. Some airlines even have services not available on some legacy carriers, such as mood lighting, found in Virgin America.