In December 2016, Ilnicki joined Aviva Premiership side Northampton Saints.[2] The tight head prop made his first appearance in a Saints shirt during their Aviva 'A' League fixture against Leicester Tigers a few days after signing for the club.[3]
Despite not making any first team appearances while with Saints, the Canadian prop helped Saints' second team the Northampton Wanderers reach the final of the Aviva 'A' League and eventually beat Gloucester United to lift the 2016/17 trophy.[4]
In May 2017, it was announced that Ilnicki would leave Saints at the conclusion of the 2016/17 season.[5] On 4 September 2017, Illnicki signed for English rivals Newcastle Falcons for the remainder of the 2017-18 season.[6]