In February 2012, Frontier Airlines cut five nonstop routes from Milwaukee. This move "reduced Frontier's daily departing flights out of Mitchell International from 32 to 18," or 56%. Frontier announced further layoffs in conjunction with this route change: up to 446 Milwaukee-area employees were affected by the job cuts that occurred between April 15 and April 30, 2012.
In April 2010, Allegiant purchased six Boeing 757-200 aircraft from Thomson Airways for flights to Hawaii with the delivery of the first two in the following months. In September 2011, Allegiant Air introduced the 757 into service from their main hub in Las Vegas. Allegiant later began using the ETOPS configured 757s for service to Hawaii. Fresno and Las Vegas were the inaugural destinations with nonstop service to Honolulu, Hawaii. Nonstop service to Honolulu was then added from Bellingham, Boise, Eugene, Phoenix (via Mesa Gateway Airport), Santa Maria, Spokane and Stockton. Nonstop service to Hawaii was also planned from Monterey, CA but was not actually operated. Allegiant then began to reduce its Hawaii service after determining that the extensive and costly maintenance check - which happens about every six years and costs upwards of $1 million - would not be efficient on the aircraft they flew to Hawaii.
Allegiant Air has been closely monitored by the FAA due to many emergency landings and aborted takeoffs. ABC interviewed a former Allegiant mechanic, who said "Dedicated steps were not being performed with maintenance manuals or even with general practices, before an aircraft is released." Many of these incidents had involved Allegiant's aging MD-80 aircraft, which as of November 2018 have been replaced by newer Airbus A320 family aircraft. 46 of the 86 aircraft have made emergency landings, all of which were on MD-80s. The average age of Allegiant's MD-80 fleet was 29 years compared to less than 13 years for its Airbus fleet.
In March 2011, Allegiant took over charter service to Wendover Airport for Peppermill Casinos, Inc. to shuttle customers to Peppermill's three casinos in West Wendover, Nevada; the Montego Bay Resort, the Rainbow Wendover and the Peppermill Wendover. Allegiant based one 150-seat, MD-80 series jet aircraft in Wendover and more than 20 employees, including maintenance, flight crews and stations personnel.