Six months into its current lease agreement with Trenton-Mercer Airport and Mercer County, Frontier Airlines’ request to extend its lease to five years has been accepted.

Under the amended terms, Frontier’s lease will be in effect from May 21, 2013 to May 20, 2018.

Frontier’s rent is $18,558 per year. In addition, the airline collects a Passenger Facility Charge from each ticket sold and passes a portion of that to the airport. Currently that amount is approximately $40,000 per month.

Denver-based Frontier first entered the Trenton-Mercer market in November 2012 with flights to Orlando, Fla., and quickly added routes to other Florida destinations of Fort Myers, Fort Lauderdale and Tampa; and New Orleans, which began Jan. 31.

In April, Frontier added nonstop service to Atlanta, Chicago, Columbus, Raleigh-Durham and Detroit from Trenton-Mercer Airport.

Mercer County has made investments to Trenton-Mercer Airport in the past several years.

An airport safety project called Engineered Material Arresting System, or EMAS, is scheduled for September. This FAA-mandated project requires the airport to close its main runway during construction and temporarily suspend flights.

Frontier Airlines worked with county administration to determine the best time of year to complete the project, indicating fall is the airline’s slowest travel season.