At least 39 people, including a police officer, died after an attacker opened fire on partygoers at Reina nightclub in the city’s Ortakoy district in the early hours of New Year’s Day.
Sixty-nine people were also hurt, with a number of foreigners among the dead and injured.
Eleven of the dead were Turkish nationals and one was a Turkish-Belgium dual-national, said ministry sources who spoke on condition of anonymity due to restrictions on talking to the media.
Seven victims were from Saudi Arabia and had travelled to Istanbul to attend New Year’s celebrations.
Three of the dead were from Lebanon and Iraq each.
Two nationals from Tunisia, India, Morocco and Jordan also died, sources said.
Kuwait, Canada, Israel, Syria and Russia each lost one citizen in the attack.
One victim remains unidentified.
Turkish officials have not yet released the names of those identified.