The nearly 5-foot-long wooden coffin was confiscated by U.S. customs officials at Miami International Airport from a Spanish merchant in 2008.
The dealer did not possess the necessary documentation to prove ownership of the artifact.
Suspecting that the object might have left Egypt illegally, U.S. authorities began an investigation.
“They determined that the coffin had left Egypt after 1970 as the earliest public record of the piece dated to 2007 when it was exhibited in Madrid,” Egypt’s Supreme Council of Antiquities said in a statement.
Arrangements are currently underway for the coffin to be handed over Hawass on March 10 in Washington, D.C., during an official gala ceremony.