Home visiting programs have demonstrated potential for tackling early deficits in children's cognitive, language, motor, and social-emotional skills, but little is known about their costs or how much the costs may vary across contexts. Using an ingredients-based approach for measuring all components of a program's costs, this study employs administrative data, survey data, GIS data, and interviews to estimate the costs for a state-run home visiting program implemented in municipalities in Ceará, Brazil - the Programa de Apoio ao Desenvolvimento Infantil (PADIN, or Child Development Support Program in English). Estimates suggest that the annual cost per child of the PADIN program was BRL 1,597 (USD 438) for 10 months of implementation in 2018. The top three cost elements are compensation for the home visitors (27 percent of total costs), compensation for state-level personnel providing technical assistance and supervision (23 percent), and compensation for municipal-level supervision (14 percent). The assembled cost data also suggest that municipalities make significant financial contributions to the program, bearing on average 38 percent of the costs of implementation. Finally, the cost data gathered for this analysis illuminate deficiencies in the current administrative data used to monitor program implementation and the need for more careful and more deliberate tracking of spending. An analysis based solely on financial records of the program would have overestimated total costs by 27 percent but also completely missed costs for key resources such as the cost of municipal-level supervisory personnel borne by the municipalities. These discrepancies underscore the importance of using the ingredient-based method to capture actual resource use.