Terror-Free Skies Act This bill requires the President to report to specified congressional committees every 180 days on the Iranian government's use of commercial aircraft and related services for illicit military or other activities during the past five years. Such report shall describe the extent to which: Iran's government has used commercial aircraft, including Iran Air, or related services to transport illicit cargo to or from Iran, including military goods, weapons, personnel, electronic parts and mechanical equipment, or rocket or missile components; the commercial aviation sector of Iran has provided support to the Islamic Revolutionary Guard Corps, Iran's Ministry of Defense and Armed Forces Logistics, the Bashar al Assad Regime, Hezbollah, Hamas, Kata'ib Hezbollah, or any other foreign terrorist organizations or entities designated on the specially designated national list maintained by the U.S. Department of the Treasury; and foreign governments and persons have facilitated such activities. If the President determines in such a report that any Iranian commercial airliner has used commercial aircraft for illicit military purposes on or after January 16, 2016, the President shall designate such airline as a specially designated national and blocked person. This bill shall cease to be effective 30 days after the President certifies that the Iranian government has ceased providing support for acts of international terrorism.