"Eight sailors will face non-judicial punishment," a US Navy official told AFP, speaking on condition of anonymity.
A ninth person involved in the case, a captain, has already been fired but will not face additional disciplinary action, the official said.
A report released today details a litany of problems in the January 12 incident, pointing out a string of leadership and training flaws.
Ten sailors were briefly held by Iran after their two boats were intercepted in Iranian waters near Farsi Island in the Persian Gulf.
Though the sailors were held for less than 24 hours, the incident was a major embarrassment for the US Navy and President Barack Obama.
The United States carefully avoided escalating the situation, maintaining a conciliatory tone with Tehran days ahead of the implementation of a historic international deal over Iran's nuclear program.