The 1995-born man plunged into the sea off the coast of Kolka. Rescuers suspect it was a suicide attempt.
"The man who jumped off the 9th deck of the ship is a 1995-born man, a Lithuanian citizen. He was unfortunately not found during the search operation," said Tallink representative Baiba Muceniece.
She revealed there were witnesses but declined further comment.
A helicopter was called to the scene after the ship issued a distress signal at 9.24 p.m. It used thermal cameras to try to find the man.
"The search lasted for several hours. As we knew both the exact time and place of the incident, in the end a decision was made not to continue the search, as no one above water could be found in that place," said Pēteris Subbota, the head of the Center for Coordinating Search and Rescue on Sea.
He said that water temperatures never stay north of plus two degrees Celsius, and unprepared individuals cannot stay alive for more than ten to fifteen minutes in such temperatures.
Subbota also said that the man jumped off the board deliberately.