This paper explores the two main reasons that explain why access to food changes by season: the variability of the cost of food and the variability of available incomes. Firstly, this paper looks at how much money is required to ensure that basic dietary needs are met. The second part describes the components of the cost of an adequate diet (local availability of food and local prices) through a methodology developed by Save the Children. The third part uses data from recent field surveys carried out by Save the Children to illustrate the variation of income available for food purchase. Finally, this paper proposes some implications for decision-makers resulting from this more nuanced understanding of variable access to food. This report compiles data from several livelihoods studies, including Household Economic Analyses (HEA) and Cost of the Diet studies, carried out in Kenya, Ethiopia, Niger, Burkina Faso, and Myanmar. Further research and improvement of methodologies would be required to complete this analysis and gain a more thorough understanding of the seasonal patterns of food affordability.