In 2014, Allgaier got a full-time Cup ride with HScott Motorsports. He returned to HScott for 2015, scoring his first top-ten finish at Bristol Motor Speedway. At the end of the year, Allgaier announced that he would move back down to the Xfinity Series to drive for JR Motorsports, owned by Dale Earnhardt, Jr. After a consistent 2016 season, he won two races in 2017.