Welcome Baby is a free and voluntary home visiting program piloted in one downtown Los Angeles Community for five years—and recently expanded to fourteen communities across Los Angeles County—that provides education and support for pregnant women and mothers of newborns. As part of its six-year evaluation of Best Start, the Urban Institute conducted a study of the cost-effectiveness of the initiative’s home visiting investment. Based on a variety of data sources, this report finds that the average cost per woman in Welcome Baby is $1,486, less than many other evidence-based home visiting programs. Using findings from the longitudinal survey, we also estimate the cost effectiveness ratios for select findings benefiting women who received Welcome Baby compared with women who did not receive home visiting. Incremental benefits are associated with costs ranging from about $14,000 to $50,000.