During the last few days of June and the first few days of July 2015, jetBlue began charging for bags in certain booking classes, leaving Southwest Airlines the only major U.S. carrier to not charge for bags. For the classes in which bag check fees are charged (generally the lowest class of fares offered; jetBlue offers 3 classes of fares), the cost is $20 for the first bag and $35 for the second, which is the lowest in the United States besides Frontier Airlines with similar prices.[62] 

In the March edition of Airways Magazine, it was announced that once jetBlue partnered with Yahoo! and with BlackBerry producer Research in Motion, that the airline would offer free, limited Wi-Fi capabilities on a single aircraft, N651JB, an Airbus A320-232 dubbed "BetaBlue". People access e-mail with a Wi-Fi capable Blackberry, or use Yahoo!'s e-mail and instant messaging with a Wi-Fi capable laptop, while in flight over the US. LiveTV in Melbourne Florida, created and operated the "BetaBlue" prototype. The "BetaBlue" system utilized the bandwidth and infrastructure of defunct Airfone.[32]

As part of its plan to stay competitive in reaction to the entry of Southwest Airlines into Denver, the company underwent a reorganization early in 2006. On April 3, 2006, Frontier created Frontier Airlines Holdings (FRNT), a holding company incorporated in Delaware to take advantage of favorable tax laws in that state. The corporate headquarters did not leave Colorado.[21]
Frontier Airlines (F9) is a Denver-based low-cost carrier. The carrier flies to about 65 destinations in the United States, Costa Rica, the Dominican Republic, Jamaica and Mexico. Its fleet of planes each feature a single Economy Class cabin. However, passengers can upgrade to Select Seating, which is located toward the front of the plane, or Stretch Seating, which features more legroom. Frontier's hub is based at Denver International Airport (DEN). An additional eight airports have been designated as focus cities. The airline has a codeshare agreement with Great Lakes Airlines.

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.[51] The A321ceo and A321neo, utilized on longer flights, features industry-standard seat pitch of 30"-32".[52] 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.[53][54] Main cabin seats are "pre-reclined" by the airline[51] and there are no televisions mounted at any of the seats in order to save weight.
Advanced Air Air Choice One Air Flamenco Air Sunshine Bering Air Boutique Air Everts Air Frontier Flying Service Gem Air Grand Canyon Airlines Grand Canyon Scenic Airlines Grant Aviation Griffing Flying Service Hageland Aviation Services Island Airways JetSuiteX Kenmore Air Key Lime Air Makani Kai Air Mokulele Airlines New England Airlines Penobscot Island Air Reliant Air Rectrix Aviation San Juan Airlines Scenic Airlines Seaborne Airlines Servant Air Southern Airways Express Star Marianas Air Surf Air Taquan Air Tradewind Aviation Tropic Ocean Airways Ultimate Air Shuttle Utah Airways Vieques Air Link Warbelow's Air Ventures Wright Air Service

On January 11, 2007, Frontier Airlines signed an 11-year service agreement with Republic Airlines. Under the agreement, Republic was to operate 17, 76-seat Embraer 170 aircraft for the former Frontier JetExpress operations. At the time the contract was canceled in April 2008, Republic Airlines operated 11 aircraft for Frontier Airlines, with the remaining six aircraft expected to join the fleet by December 2008. With the integration of Republic aircraft, the 'JetExpress' denotation was removed. Subsequent to the cessation of Horizon's services for Frontier in December 2007, all flights operated by Republic were sold and marketed as "Frontier Airlines, operated by Republic Airlines." The first market created specifically for the Embraer 170 was Louisville, Kentucky, which began on April 1, 2007. Service to Louisville was suspended in August 2008 but restarted in April 2010.[citation needed]
Following the February 2007 incident in which the airline was forced to cancel nearly 1,700 flights due to winter storms, jetBlue's board of directors replaced founder and Chief Executive Officer David Neeleman with Dave Barger.[21] He had politicked the board, while Neeleman was busy publicly apologizing. Barger's ascendancy caused widespread demoralization in the ranks.[22] He became JetBlue's new Chief Executive Officer on May 10, 2007.[23] Neeleman, the company's founder and largest individual investor, became a nonexecutive chairman as a result of the change.[24]
In 2014, Frontier announced it would be transitioning into an ultra-low cost carrier.[47] 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.[48] 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.[49]
Frontier Miles is the frequent-flyer program for Frontier Airlines, replacing the EarlyReturns program, which existed from 2003 to 2018.[70] Frontier Miles can be earned by flying Frontier Airlines, using the Frontier Airlines World MasterCard, or by spending at partner hotels, car rental chains, cruises, and merchants.[71] Frontier Miles can be redeemed for flights, magazine subscriptions, and car rentals.[72] Since February 2019, hotel stays are also part of the redemption options.[73]
In 2008, jetBlue partnered with Irish flagship carrier Aer Lingus to allow passengers to switch between airlines on a single ticket for flights with connections in New York–JFK or Boston Logan. Unlike traditional codeshare agreements, the companies cannot sell seats on each other's flights, so customers initiate the purchase on one airline's website and then are transferred to the other site to complete the transaction.[105][106]
Buffalo to Orlando Buffalo to New York Buffalo to Fort Lauderdale Buffalo to Fort Myers Buffalo to Boston Seattle to New York Chicago to New York Syracuse to Orlando Phoenix to Boston New York to Los Angeles New York to Orlando Los Angeles to New York Houston to New York Orlando to New York New York to Las Vegas Boston to Las Vegas New York to Chicago Burlington to Orlando New York to San Francisco San Francisco to New York
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