Background Little attention has been paid to the question of how to finance the costs of scaling up MNCH care and the likely availability of funds. Methods Past health expenditure (2000 – 2005) was analysed through the National Health Accounts of 57 high priority countries. We projected likely availability of funding for the period 2006 – 2015 under two scenarios (business as usual and public commitments). We estimated the financing gap by comparing the share of projected total health expenditure dedicated to MNCH with the WHO costing model for scaling MNCH interventions. Findings The vast majority of countries spent less than 50 US$ per person on health in the year 2005. Under the business as usual scenario, the financing gap for the period 2006-2015 for low income countries is more than US$ 38.5 billion. Under the public commitments scenario, the gap for low income countries (excluding India) falls to just under US$ 18.3 billion. In lower middle and upper middle income countries the projected financing is estimated to meet costs under both scenarios. Interpretation The volume of financing resources for the majority of low income countries will not be adequate to meet MDGs 4 and 5, even under optimistic assumptions. The financing sources required to “fill the gap” will depend on country context and needs. Additional funds need to be effectively targeted to MNCH services. Lower and upper middle income groups are likely to have sufficient funds. Their domestic policies for MNCH fund allocation will be paramount.