Unfortunately, that was as good as it could get for Biffle as he faded outside the top twenty in points. He struggled mightily before picking up a second-place finish in the 2015 Coca-Cola 600, after starting fourth. He went on to pick up a fifth-place finish at Pocono in the 2015 Windows 10 400 and a fourth-place at New Hampshire in the 2015 Sylvania 300, finishing twentieth in points.