Child support is a key resource for children living apart from their fathers, yet little is known about how child support changes over the course of childhood, particularly for different types of child support and by parents' relationship status at the child's birth. This study uses longitudinal data from the Fragile Families and Child Wellbeing Study to examine trajectories of formal, informal, and total cash and in-kind support provided by nonresident fathers for children from birth to age 15. We find that all fathers initially pay more informal than formal support, but informal support falls precipitously over the first few years of separation while formal support gradually increases, becoming the largest source of cash support over time. We also find that in-kind support, initially the most common form of support, also declines as time living away from the child increases, but remains an important resource over the entire period.