 On 14 January 2019, Wagner and Huddersfield Town agreed to terminate his contract by mutual consent, with the team in last place and eight points from safety.On 9 May 2019, Wagner was appointed as manager of Bundesliga club Schalke 04 on a three-year contract until 30 June 2022.In the second half of the 2019–20 season, Schalke set a new club record of 16 league games without a win between 25 January and 27 June 2020.