What's the Best Low-Cost Airline?

For many travelers, cheap airfare is a vital part of an affordable summer trip. Smaller airlines known in the industry as low-cost carriers, or LCCs, traditionally try to undercut legacy carriers such as Delta Air Lines with low operating costs, limited routes, and no-frills service. With most airlines adding fees in recent years, some budget carriers now offer more free amenities than legacy carriers and similar ticket prices. Others stick to a business model that sets a cheap base fare and makes up the difference by charging fees for nearly everything else. This can make it difficult to judge the total cost of a trip, not to mention value for the money. To help consumers make the right choice, Cheapism.com compared fees, seating, baggage handling, customer service, number of flights, and amenities to determine the best U.S.-based budget airlines.

Related: 10 Cheapest U.S. Cities for Summer Air Travel

Spirit Airlines flies more than 400 daily flights to nearly 60 destinations and unashamedly markets itself as a bare-bones budget airline. It offers low base fares then charges fees for everything else. The pick-and-choose model could be a money-saver for some savvy travelers, but others get caught off-guard by fees simply to pick a seat (sitting with a friend or loved one can be guaranteed only at a price), bring a carry-on (only personal items no larger than a backpack are included in the fare), print a boarding pass, or even enjoy a drink of water during a flight. The prices for some of these add-ons are cheapest at the time of booking and most expensive at the airport gate, so frugal consumers should try to decide how many bags they'll need, for example, well in advance. The austere flight experience and avalanche of associated fees lead many travelers to give the airline bad reviews; it's one of the most pilloried in the industry.

While Allegiant Air flies to more than 100 destinations, it has only 85 planes, as many routes are seasonal and not serviced daily. The leisure airline routes passengers through 19 "focus cities" located primarily in California and Florida, with other major hubs in Nevada and Arizona. This hub-and-spoke model can cost travelers, because Allegiant charges fees per flight segment, so the charges could apply more than once if the itinerary includes layovers. Allegiant's approach to pricing relies heavily on fees, offering low ticket prices and then charging for additional services. This includes carry-on bags, which incur a fee of $15 to $50 ($75 for gate-checked bags), as well as seat selection, credit-card processing, printing a boarding pass, and in-flight soft drinks and juice. Passengers unfamiliar with the airline can quickly rack up enough fees to erase any potential savings they found when comparing ticket prices.

A small airline with just 58 planes, Denver-based Frontier Airlines flies to nearly 60 destinations in the United States, Dominican Republic, Mexico, and Jamaica. Complaints are common among travelers, and industry rankings don't rate Frontier favorably, but the low-cost airline does have its fans. As with Spirit and Allegiant, there are additional fees to pick a seat, bring a carry-on bag, or buy a soft drink onboard. Frontier passengers should be sure to pay as many fees as possible when booking at FlyFrontier.com, as many increase if you pay later. One bright spot is relatively wide coach seats for a budget carrier, although they lack much legroom ("stretch" seating costs extra) and entertainment systems.

Amenity-packed Virgin America gives all passengers soft drinks and coffee, entertainment options, power outlets, and snazzy features such as mood lighting and seat-to-seat chat options on touchscreen entertainment systems. Wi-Fi is available for a fee, and as many as 10 bags can be checked at $25 each (most airlines charge more starting with the second bag). Travelers have the option to pay extra to guarantee preferred seating choices or priority boarding. These charges can add up, but the airline has placed first in several traveler and industry awards for its category. With only about two dozen destinations and about 60 aircraft, Virgin America is too small to top our list. It was acquired by Alaska Airlines in April, but Alaska's CEO has said the Virgin America brand may be preserved and operated separately.

JetBlue Airways sets itself apart from the other U.S.-based low-cost carriers with amenities such as snacks, power outlets for each seat, entertainment, and Wi-Fi all included in the fare. However, the airline now charges between $20 and $25 for a checked bag with the lowest fares to domestic locations. Additional comfort may go some way toward making extra fees more palatable, as JetBlue's economy seats are larger and offer more legroom than seats on many other budget carriers, and JetBlue consistently receives top marks for quality and customer satisfaction in consumer and industry reviews and reports. JetBlue flies to nearly 100 destinations, with about 925 daily flights on its 219 aircraft. It has hubs in New York (JFK); Boston; Fort Lauderdale and Orlando, Florida; Long Beach, California; and San Juan, Puerto Rico. One-third of its flights service the Caribbean, Latin America, and other international cities.

Southwest Airlines is the largest domestic low-cost carrier. It has more than 700 planes in its fleet and operates more than 3,800 flights each day to nearly 100 destinations, including Puerto Rico and the Caribbean, Mexico, and Latin America. In addition to its size, Southwest stands out for letting passengers take two free checked bags, waiving ticket change fees (passengers pay only the difference in cost between tickets), and offering free seatback entertainment and snacks. Certain flights also offer Wi-Fi access for an additional price of $8 per device for all-day service. Although it doesn't place at the top, Southwest makes strong showings in industry and traveler reviews and rankings for customer satisfaction. With creative leeway to "have fun on the job," airline staff have treated passengers to safety instructions delivered as a rap or stand-up routine.