Hill, 24, can practice with the Ravens in training camp and throughout the preseason, but he won't be available in the regular season until Oct. 13. The Ravens currently have Darian Stewart penciled in as the starting free safety.
Hill played for the Giants the past two seasons and started 10 games last season. He has been suspended three times by the NFL, once for using a performance-enhancing drug that he said was Adderall and twice for violating the league's substance abuse policy.
The Giants released Hill on June 2, just two days after the NFL handed down his current suspension.