In March 2015, Sewell announced his opening slot on Ed Sheeran‘s Australian tour. He joined Sheeran on 13 dates throughout Australia. Come June 2015, Live Nation confirmed that Sewell would join Maroon 5 on their September tour as well as posting several tour dates.
In March 2015, he was picked as Elvis Duran‘s Artist of the Month and was featured on American TV network NBC‘s Today show hosted by Kathy Lee Gifford and Hoda Kotb and broadcast nationally across the United States where he performed live his single “Start Again“. In November 2015, at the ARIA Music Awards of 2015, Sewell won Song of the Year for “Start Again”. In February 2016, Sewell released “Remind Me” as the final single from All I Know. The following month, Coca-Cola released a song and video for their new campaign, “Taste the Feeling“. It features Sewell’s vocals and production from Avicii.
On 18 May 2018, Sewell released the “Ghosts & Heartaches” single, containing two songs—”Come Clean” and “Healing Hands”