The high proportion of people unable to afford nutrient-adequate diets has been recognised as a global challenge. For policies and programmes that aim to improve food security and nutrition, it is essential to know the magnitude of the gap between food expenditure and the lowest cost of meeting nutrient needs, i.e., the affordability gap. Using data and examples from Fill the Nutrient Gap analyses in Dominican Republic, Ethiopia and Indonesia, the paper shows how the affordability gap can be used to inform the design of social assistance programmes to have a bigger contribution towards making nutrient-adequate diets more affordable. The affordability gap indicator can help assess adequacy of the transfer value and inform the design of the benefits package to become more comprehensive through linkages with nutrition interventions.