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.
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. In June 2016, Frontier re-established service to Port Columbus International Airport. 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. In December 2017, Frontier began service to Buffalo, New York, with service to Denver, Colorado, and Florida, including Miami, Fort Myers, Orlando, and Tampa.
In March 22, 2010, jetBlue turned down incentives from the City of Orlando and announced its headquarters would keep its Forest Hills office, start leasing and using a new office in the Brewster Building in Long Island City, New York. in Queens Plaza in Long Island City, move its headquarters there in mid-2012, and start a joint branding deal with New York State using the iconic I Love NY logo.
In February 2002, the airline launched its first regional product, Frontier JetExpress, initially operated by Mesa Airlines using CRJ-200 regional jets. Similar to "express" operations of other carriers, Frontier JetExpress was targeted for markets to and from Denver that do not generate traffic sufficient to support Frontier's smallest mainline jet, the Airbus A318, but could still offer lucrative business with a smaller jet.
In November 2012, Frontier started low-frequency service between Orlando International Airport and Trenton–Mercer Airport near Trenton, New Jersey, which, at the time, had no commercial service. Frontier later expanded service several times from Trenton, and as of June 2016 services 11 destinations. Frontier currently bases three aircraft in Trenton. Trenton Mercer Airport lies roughly equidistant between Philadelphia International Airport and Newark Liberty International Airport.
On March 22, 2010, jetBlue announced it would remain in the New York City area, in Long Island City, because of the airline's historical links to the city, the cost of staff relocations, the airline's desire to retain access to financial markets, and because Aer Lingus and Lufthansa, jetBlue's marketing partners, fly into JFK Airport. jetBlue planned to combine its Forest Hills and Darien, Connecticut offices, together about 1,000 employees, into about 200,000 square feet (19,000 m2) in the Brewster Building by mid-2012.
Denver to Las Vegas Detroit to Denver Chicago to Denver Seattle to Denver Denver to New York Denver to Chicago Atlanta to Denver Dallas to Denver Denver to Phoenix Denver to Los Angeles Houston to Denver Denver to Orlando New York to Denver Denver to Atlanta Phoenix to Denver Denver to San Diego Orlando to Denver Tampa to Denver Denver to San Francisco Denver to Seattle
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
jetBlue experienced its first-ever quarterly loss during the fourth quarter of 2005 when the airline lost $42.4 million, enough to make them unprofitable for the entire year of 2005. The loss was the airline's first since going public in 2002. JetBlue also reported a loss in the first quarter of 2006. In addition to that, jetBlue forecasted a loss for 2006, citing high fuel prices, operating inefficiency, and fleet costs. During the first quarter report, CEO David Neeleman, President Dave Barger, and then-CFO John Owen released JetBlue's "Return to Profitability" ("RTP") plan, stating in detail how they would curtail costs and improve revenue to regain profitability. The plan called for $50 million in annual cost cuts and a push to boost revenue by $30 million. jetBlue Airways moved out of the red during the second quarter of 2006, beating Wall Street expectations by announcing a net profit of $14 million. That result was flat when compared to jetBlue's results from the same quarter a year before ($13 million), but it was double Wall Street forecasts of a $7 million profit, Reuters reports. The carrier said cost-cutting and stronger revenue helped it offset higher jet fuel costs. In October 2006, jetBlue announced a net loss of $500,000 for Quarter 3, and a plan to regain that loss by deferring some of their E190 deliveries and by selling 5 of their A320s.
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.
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.
JetBlue Technology Ventures (JTV)  is a wholly owned subsidiary of JetBlue that was established in February 2016. JTV is the venture capital arm of JetBlue that invests in and partners with early-stage startups in the travel, hospitality, and transportation space. Its mission is to improve the end-to-end experience of travelers everywhere. As of November 2018, JTV has invested in 21 startups, including hybrid planes, machine learning algorithms, and ground transportation. Investments range in size from $250,000 to $1 million.