If you are uncertain about the routes that these low-cost carriers fly, check them out online. For instance, JetBlue serves many of the major U.S. cities, particularly on the East Coast. It also has numerous vacation destinations in Central and South America and the Caribbean; Southwest serves most major U.S. cities as well as a few in Central America and Puerto Rico; Frontier serves most major U.S. cities as well as vacation spots in Mexico, Jamaica and the Dominican Republic; Allegiant Air's focus is transporting leisure travelers to warm vacation destinations like Punta Gorda, Tampa Bay, Las Vegas, Orlando, Los Angeles and Phoenix.
Fare comparison sites are usually the first stop for people
to give them a shot.
You're not crazy for thinking that a flight price has changed after searching it a few times in your web browser. Based on the cookies in your browser, flight prices do increase when a particular route is repeatedly searched, as the site wants to scare you into booking the flight quickly before prices get even higher. Always search for flights in incognito or private browsing mode to see the lowest prices.