Canberra
Bateman signed with the Canberra Raiders for 2019 and 2020, with a third-year option in his favour, on 8 August 2018. In round 19 of the 2019 NRL season against the Penrith Panthers, Bateman scored a try in the dying minutes to seal a 30–18 victory for the visitors away from home. The win cemented Canberra's position in the top 4 of the competition.
At the end of the 2019 regular season, Canberra finished 4th on the table and qualified for the finals. In the qualifying final against Melbourne, Bateman scored the winning try with just 3 minutes remaining. Canberra staged an upset victory at AAMI Park winning 12-10 and securing a home preliminary final. In the preliminary final against South Sydney, Bateman played at second-row as Canberra won the match 16–10 at Canberra Stadium and qualified for their first grand final in 25 years. On 2 October, Bateman was named as the 2019 Dally M second-rower of the year at the Dally M Awards ceremony.
Bateman played at second-row for Canberra in the 2019 NRL Grand Final as they were defeated 14–8 by the Sydney Roosters at ANZ Stadium.
In February, it was revealed that Bateman would miss the first six weeks of the 2020 NRL season after undergoing shoulder surgery.
On 31 June, it was announced that he would be departing the Canberra Raiders at the end of the season, With NRL Club, the Canterbury-Bankstown Bulldogs And His former side, The Wigan Warriors interested in his services.
Bateman played 11 games for Canberra in the 2020 NRL season. He featured in all three of Canberra's finals matches, including Melbourne's preliminary final loss. After the game had concluded, a visibly emotional Bateman thanked everyone at Canberra and stated it would be hard to leave the club.
In August 2021, it was revealed that Bateman had been involved in a fistfight with then-Canberra player Curtis Scott. The incident was not reported to
the police and the matter was sorted behind closed doors but the story came to light after Scott's termination by the Canberra club.