The initial JetExpress partnership with Mesa ended in January 2004, when Horizon Air was selected to operate the routes. Horizon utilized slightly larger CRJ-700 regional jet aircraft on these routes. In August 2006, Frontier and Horizon ended their partnership.[64] While Frontier was generally pleased with Horizon's operation, the carrier decided that it needed to revisit the agreement and find a provider with additional regional jets to grow the operation. The last of the CRJ-700's was returned to the Horizon Air fleet on November 30, 2007.
In late 2009 Republic began to consolidate administrative positions and moved 140 jobs from the Frontier Airlines Denver headquarters to Indianapolis, Indiana.[29] Shortly after that, in January 2010, Republic Airways announced that it would move all of its executives to Indianapolis.[30] In February the Denver Business Journal stated that the headquarters would be moved "soon".[31] Despite this, according to the Denver Business Journal, Frontier Airlines will still maintain a local headquarters in Denver to house Training, Marketing, Customer Reservations, and Scheduling & Planning teams after extending its lease on the building through 2020.[citation needed]
In an effort to focus on regional contract flights for major carriers, Republic Airways Holdings announced in January 2012 its intention to sell or spin off Frontier.[38][39] On January 26, 2012, Republic Airways Holdings appointed former US Airways and Gate Gourmet CEO David Siegel as President and CEO of Frontier Airlines. Republic also added new senior officers for Frontier's finance and commercial team, among other changes in the executive leadership team. Siegel and other Frontier executives moved to Denver where Frontier is headquartered in order to facilitate management of all aspects of Frontier during its separation process from Republic and continue its transformation into an ultra-low-cost carrier.[13]
The initial JetExpress partnership with Mesa ended in January 2004, when Horizon Air was selected to operate the routes. Horizon utilized slightly larger CRJ-700 regional jet aircraft on these routes. In August 2006, Frontier and Horizon ended their partnership.[64] While Frontier was generally pleased with Horizon's operation, the carrier decided that it needed to revisit the agreement and find a provider with additional regional jets to grow the operation. The last of the CRJ-700's was returned to the Horizon Air fleet on November 30, 2007.
jetBlue expanded service to the Caribbean, including to St. Maarten and Puerto Plata commencing January 10, 2008. With these additional destinations, jetBlue serves a total of twelve Caribbean/Atlantic destinations including Aruba; Barbados; Bermuda; Cancún; Nassau; Aguadilla; Ponce; San Juan, Puerto Rico; Santiago; and Santo Domingo, Dominican Republic.[citation needed]
JetBlue Airways Corporation (NASDAQ: JBLU), stylized as jetBlue, is an American low-cost airline headquartered in New York City. A major air carrier and the sixth-largest airline in the United States. JetBlue is headquartered in the Long Island City neighborhood of the New York City borough of Queens, with its main base at John F. Kennedy International Airport. It also maintains corporate offices in Cottonwood Heights, Utah[6][7] and Orlando, Florida. 

In February 2015, Frontier announced that they will begin service to several destinations from Atlanta adding the airport as a focus city. In July, Frontier also began decreasing service from Washington Dulles International Airport removing the airport as a focus city. In early 2016 Frontier announced major route expansion from airports nationwide including Atlanta, Chicago, Cincinnati, Cleveland, Orlando, and Philadelphia.[55] In June 2016, Frontier re-established service to Port Columbus International Airport.[56] In May 2017, the airline announced opening a new crew base in Las Vegas in the fall 2017 to improve operational reliability and potentially create new jobs in Las Vegas.[57] In December 2017, Frontier began service to Buffalo, New York, with service to Denver, Colorado, and Florida, including Miami, Fort Myers, Orlando, and Tampa.[58]

In July 2013, Frontier started service from New Castle Airport near Wilmington, Delaware to five destinations,[41] which Frontier markets as Wilmington/Philadelphia. Again, this airport had no commercial service prior to Frontier's entry.[citation needed] New Castle Airport lies roughly 30 miles southwest of Philadelphia International Airport and 75 miles northeast of Baltimore–Washington International Airport.[citation needed]
^ Jump up to: a b c "JetBlue 2017 Annual Report" (PDF). p. 8. Retrieved 2018-09-19. We are a predominately point-to-point system carrier, with the majority of our routes touching at least one of our six Focus Cities: New York, Boston, Fort Lauderdale-Hollywood, Orlando, Long Beach and San Juan, Puerto Rico. During 2017, over 92% of our Customers flew on nonstop itineraries.
×