Although Stephenson was originally returned to the Hershey Bears to begin the 2017–18 season, he was recalled on October 24, 2017, after playing six games. Through those six games, Stephenson led the team with five goals and tied for the team lead with six points. As a result of numerous injuries to the Capitals lineup, Stephenson played on their top line during a 6–2 loss to the Vancouver Canucks on October 26. During the game, he recorded his first career NHL goal against goaltender Anders Nilsson. As a result of his performance, Stephenson was placed on a line with Lars Eller and Tom Wilson at the end of October which produced five goals and 13 points through six games. However, his production slowed down as the season continued and he snapped a 28-game goal drought with two goals in a 5–3 win over the Philadelphia Flyers. Throughout the season, Stephenson became a mainstay on the Capitals' bottom-six forwards line and spent time on the penalty kill and in 3-on-3 overtime. He finished the season playing an average of 87:20 on the penalty kill, the fifth-most amongst Capitals forwards. As the Capitals qualified for the 2018 Stanley Cup playoffs, he was expected to play a major role in their post-season run.
