"Peer-to-peer payments is never going to be a source of profit for anyone," Marcus said in an interview on CNBC's "Squawk Alley."
"We're not interested in building a payments business. We're interested in trying to build the best possible experience."
Marcus, who is Facebook's vice president of messaging products, spoke to CNBC in an interview from the Code Conference in Rancho Palos Verdes, California. He was formerly president of PayPal.