The issue raises questions about what will happen to the detainee and others like him, given that President Barack Obama has ruled out sending any more terror suspects to Guantanamo Bay and the United States does not want to create a holding center for IS captives in Iraq.
US officials declined to identify the detainee to The Times, or say how much he had cooperated.
The detainee was captured by elite special operations troops who deployed to Iraq in recent weeks and whom the Pentagon calls a specialized expeditionary targeting force, or ETF.
The Times said the 200-member special operations team is made up of many Delta Force commandos.
Though it is small in number, it represents the first major US ground combat force since the official withdrawal of US troops at the end of 2011.
Another 3,870 or so US troops are in Iraq on a mission to train and support Iraqi forces fighting the IS group.
The Pentagon declined to confirm the report, saying it would not discuss the ETF's operations.
"One of the goals of the ETF is to capture ISIL leaders," he added, using an alternative acronym for the IS group.
"Any detention would be short-term and coordinated with Iraqi authorities."
Officials told The Times that US interrogators were with the detainee at a temporary detention facility in Erbil in northern Iraq.
He would eventually be handed over to Iraqi or Kurdish officials.
"We are not back in the business of having long-term detainees," a US defense official told.
