This study examined the relationships among non‐resident fathers' involvement, mothers' parenting and parenting stress, and children's behavioural and cognitive development in low‐income single‐mother families. Based on the theoretical concepts of father involvement in terms of accessibility, responsibility and interaction, this study operationalizes fathers' involvement with three different measures: (i) fathers' frequency of contact with their children; (ii) fathers' amount of child support payment; and (iii) fathers' quality of parenting. Analyses used the first three waves of longitudinal data from a subsample of single and non‐cohabiting mothers with low income in the Fragile Families and Child Wellbeing Study. Results suggest that non‐resident fathers' child support payment is indirectly associated with both children's behaviour problems and cognitive development. Fathers' parenting is also found to be indirectly associated with children's behaviour problems. The findings further suggest that those estimated associations are transmitted through mothers' parenting. The expected associations between fathers' contact and child outcomes are not found in this sample. The study also discusses the policy and practice implications of its findings.