On March 19, 2008, jetBlue added Orlando, Florida as a gateway focus city to international destinations in the Caribbean, Mexico, and South America. New international routes from Orlando International Airport include Cancún, Mexico, Bridgetown, Barbados, Bogotá, Colombia, Nassau, Bahamas, San José, Costa Rica, and Santo Domingo, Dominican Republic. In conjunction with the addition of new routes the airline will continue significant expansion of operations at Orlando International Airport including a planned 292-room lodge that will house trainees attending the existing "JetBlue University" training facility (opened in 2015).
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.
Scheduled service began on October 15, 1998, between Las Vegas and the airline's original hub in Fresno, California, at the Fresno Yosemite International Airport, with Douglas DC-9-21 and McDonnell Douglas DC-9-51 jetliners. During the second half of 1999, the airline was operating nonstop flights between Fresno and Las Vegas, Burbank and Lake Tahoe, and Las Vegas and Lake Tahoe as well as flying one-stop direct service between Fresno and Lake Tahoe via Las Vegas. Shortly after WinAir Airlines closed in 1999, Allegiant Air opened a small hub in Long Beach, CA (LGB) and in 2000 was operating nonstop flights to Fresno and Las Vegas in addition to Fresno-Las Vegas nonstop service. Later in 2000, Allegiant continued to expand and was operating the only nonstop jet service between Lake Tahoe Airport from Long Beach in addition to operating new flights into Portland, Oregon and Reno with Portland-Reno and Reno-Fresno nonstops and direct one-stop service between Portland and Fresno via Reno. Citing higher fuel costs as a major factor, Allegiant filed for Chapter 11 bankruptcy protection in 2000.
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. 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.