Munoz is expected to return to the job at the end of the first quarter of 2016.
"I feel great! I'm planning to increase my involvement," Munoz said on the call. "I will certainly be back full time by the end of the first quarter if not sooner."
Munoz has been on medical leave since suffering a heart attack in October with Brett Hart taking over as interim CEO until his return.
On the call, Munoz thanked Hart and the United team for their performance during his absence.
Munoz received the transplant on January 6 and is reportedly doing well.
"Given Mr. Munoz's excellent physical condition and the rapid pace of his recovery prior to the transplant, we expect a quick recovery and a return to his duties as CEO," Northwestern Medicine chief of cardiac surgery Patrick M. McCarthy, MD, said in a statement following the procedure.
Munoz joined United as its CEO just week prior to his heart attack following the September resignation of longtime CEO Jeff Smisek.