The reward includes $10 million for the identification or the location of leaders of the group, and $5 million for information that results in the arrest of anyone conspiring with Conti.
"In offering this reward, the United States demonstrates its commitment to protecting potential ransomware victims around the world from exploitation by cyber criminals," State Department spokesman Ned Price said.
The FBI estimates more than 1,000 victims have made in excess of $150 million in ransomware payments to the Conti group, making this to be the costliest ransomware payment to a group ever to be documented.
Earlier last year, the FBI said that Conti was responsible for striking 16 medical and first responder networks in the United States. The same group was blamed for an attack in April on Costa Rica's tax and customs platforms, impacting the Central American country's foreign trade.
In February, the Conti group vowed to attack enemies of the Kremlin if they respond to Russia's invasion of Ukraine.