Returning to North Dakota for the 2015–16 season, Schmaltz centered a line with Drake Caggiula and Brock Boeser, a trio referred to as the "CBS line". He was named the NCHC Player of the Month for November after recording two goals and 13 assists in eight games, including five multi-point outings. With five goals and 19 assists in 19 conference games, Schmaltz was an All-NCHC honorable mention at the end of the season. Altogether, he had 11 goals and 46 points in 37 games, third on the team behind his linemates Caggiula and Boeser. The Fighting Hawks tied with Denver for third place in the 2016 NCHC Tournament, while Schmaltz, who scored two of the team's three goals in the Frozen Faceoff, was named to the All-Tournament Team. North Dakota once again played in the NCAA Tournament, where they faced Denver in the Frozen Four semifinals. Deadlocked at 2–2 with 60 seconds remaining in regulation, Schmaltz scored the game-winning goal, with North Dakota winning the game 4–2 shortly after on an empty net goal from Rhett Gardner. He added an assist in North Dakota's 5–1 victory over Quinnipiac, which gave the Fighting Hawks their first NCAA championship title since 2000. After his sophomore season, Schmaltz elected to leave North Dakota and signed a three-year, entry-level contract with the Blackhawks. In 75 games across two collegiate seasons, he recorded 16 goals and 56 assists.
