There is growing evidence of the effectiveness of early childhood interventions to improve the growth and development of children. Although, historically, nutrition and stimulation interventions may have been delivered separately, they are increasingly being tested as a package of early childhood interventions that synergistically improve outcomes over the life course. However, implementation at scale is seldom possible without first considering the relative cost and cost-effectiveness of these interventions. An evidence gap in this area may deter large-scale implementation, particularly in low- and middle-income countries. We conduct a literature review to establish what is known about the cost-effectiveness of early childhood nutrition and development interventions. A set of predefined search terms and exclusion criteria standardized the search across five databases. The search identified 15 relevant articles. Of these, nine were from studies set in high-income countries and six in low- and middle-income countries. The articles either calculated the cost-effectiveness of nutrition-specific interventions (n = 8) aimed at improving child growth, or parenting interventions (stimulation) to improve early childhood development (n = 7). No articles estimated the cost-effectiveness of combined interventions. Comparing results within nutrition or stimulation interventions, or between nutrition and stimulation interventions was largely prevented by the variety of outcome measures used in these analyses. This article highlights the need for further evidence relevant to low- and middle-income countries. To facilitate comparison of cost-effectiveness between studies, and between contexts where appropriate, a move towards a common outcome measure such as the cost per disability-adjusted life years averted is advocated. Finally, given the increasing number of combined nutrition and stimulation interventions being tested, there is a significant need for evidence of cost-effectiveness for combined programmes. This too would be facilitated by the use of a common outcome measure able to pool the impact of both nutrition and stimulation activities.