The program for pre-screened passengers was launched in October 2011 and is available in 26 U.S. airports, with nine more airports expected by the end of 2012, USA Today reported Friday.
The dedicated security lanes have screened 2.7 million passengers, said TSA spokesman David Castelveter.
"Clearly we expect to broaden the array of carriers involved with the program," he said.
United Airlines announced it would begin offering pre-checks at their hubs at Newark, N.J., and Dulles Airport outside Washington.
"Everyone has recognized that the security screening process has become time-consuming and comes across as a pain point, said Alex Marren, senior vice president of network operations and United Express, adding that pre-check fliers travel through security 2 1/2 times faster than other passengers.