On November 8, 2017, Stewart-Haas Racing announced Almirola as the driver of the No. 10 Ford Fusion for the 2018 season. Almirola was leading the 2018 Daytona 500 when on the race's last lap Almirola and eventual race winner Austin Dillon collided, resulting in Almirola crashing into the outside wall and finishing 11th. His consistency throughout the regular season brought him to the playoffs. At the inaugural Charlotte Roval race, Almirola was barely able to advance to the Round of 12 with a 19th-place finish after slamming the outside wall while avoiding William Byron, who cut a tire in front of him. He had a strong running at the fall Dover race until he got loose exiting the turn and collided with Brad Keselowski, which caused a multi-car pileup that took out Keselowski, Martin Truex Jr., and Alex Bowman. One week later, Almirola and Stewart-Haas Racing dominated the fall Talladega race. On the final lap, Almirola was running 2nd until his teammate Kurt Busch ran out of gas. Almirola scored his second career cup win, locking him into the Round of 8. Despite finishing fourth at Phoenix, Almirola was eliminated in the Round of 8. He finished the season fifth in the points standings, the highest finish of his career.