New Orleans also re-signed S and special teamer J.T. Gray to a two-year, $4 million deal that includes $2 million guaranteed.
Gray was scheduled to be a restricted free agent.
Onyemata, 28, is a former fourth-round pick of the Saints back in 2016 out of Manitoba College. He finished his four-year, $2.88 million contract and was set to be an unrestricted free agent for the first time in his career before signing an extension with the Saints in 2020.
In 2020, Onyemata appeared in 15 games for New Orleans and recorded 44 total tackles, 10 tackles for loss, 6.5 sacks, one interception and two pass defenses. Pro Football Focus had him rated as the No. 7 interior defender out of 125 qualifying players.