In July 2017, Frontier announced 21 new cities and 84 new routes. These cities include Buffalo, Charleston, S.C., Pensacola, Jackson Hole, Palm Springs, San Jose, Reno, Little Rock, and Tulsa. Destinations that saw a significant bump-up in new service include Austin, Cincinnati, Long Island/Islip, N.Y., Miami, Orlando, Providence, San Antonio, and Tampa.
In October 2013, Republic Airways Holdings entered into an agreement with private equity firm Indigo Partners to sell Frontier Airlines for approximately $145 million. According to Indigo, the transaction would further Frontier's evolution into an ultra-low-cost carrier. In December 2013, Indigo Partners LLC, through an affiliate, completed the purchase of Frontier Airlines from Republic Airways Holdings. The airline's headquarters will remain in Denver. Republic Airways Holdings subsidiary Republic Airlines no longer flies Embraer 190 aircraft on behalf of Frontier, as of January 1, 2014.
In March 2010, Allegiant purchased six used Boeing 757-200 jetliners as part of plans to begin flights to Hawaii, with deliveries from early 2010 to the fourth quarter of 2011. It gained the approval for type with the FAA in July 2011, and then worked with the FAA to obtain the appropriate ETOPS rating in order to be able to serve Hawaii. Allegiant no longer operates nonstop service to Honolulu from Las Vegas.
At 19″ wide, the middle seats in the airline's Airbus 321s, A320s, and A319s are wider than the window and aisle seats and, as of July 2015 when the airline began installing them, are the widest middle seats of any airline in the U.S. The A321ceo and A321neo, utilized on longer flights, features industry-standard seat pitch of 30"-32". The airline uses a seat pitch of only 28″-29", the tightest seat pitch of any airline in the United States, on their A320ceo and A320neo, typically operated on shorter flights. Frontier Airlines has 28"-31" on the Airbus A319, which they are phasing out. Main cabin seats are "pre-reclined" by the airline and there are no televisions mounted at any of the seats in order to save weight.
In 2014, Frontier announced it would be transitioning into an ultra-low cost carrier. Frontier will also cut several flights and jobs at their Denver hub and transition them to different markets. On January 16, 2015 Frontier announced that it will close both its Denver and Milwaukee call centers, laying off 1,300 employees and outsourcing the jobs to call center company, Sitel, which operates a large call center for Frontier in Las Cruces, New Mexico. As part of its transition to an ultra-low-cost airline, Frontier Airlines joined Spirit and Allegiant in June 2015 in removing its toll-free telephone number for customer service.
We arrived at the airport at 5:15 for our 7:15 flight. After two delays we received a text message from the company that the flight had been canceled. 35 minutes later an employee finally came out to announce the cancellation. As we started asking questions like “will we get our money back” or “do you have any more flights going out we can get on” each time a piece of paper was picked up and shaken in our faces and were told to read the paper just like everyone else. Worst service ever!!!!!! We were all states away from home with no where to go and no help from frontier. And our refund could be expected within two weeks. All I could think of is how I hoped everyone there could find funds to purchase another ticket to where they were going. Because last minute tickets are crazy expensive. I will never fly frontier again!!!! They gave me a $100 voucher off my next flight with them but I’ll never use it!!!
A November 2016 analysis by the Tampa Bay Times noted that Allegiant's planes were four times more likely to have in-flight failures than other major US airlines. A 60 Minutes report by CBS News in 2018 continued to investigate the issues first raised by the Tampa Bay Times. Public records cited in the investigation found that the airline had more than 100 serious mechanical incidents between January 1, 2016 and October 31, 2017, including "mid-air engine failures, smoke and fumes in the cabin, rapid descents, flight control malfunctions, hydraulic leaks and aborted takeoffs." Other public records further revealed that Allegiant aircraft, on average, were nearly three and a half times more likely to have mid-air breakdowns than American, United, Delta, JetBlue and Spirit.