The impact of the global economic crisis caused by the COVID-19 pandemic will not affect all children equally: those in poorer households and children who are disadvantaged face the most serious consequences. As parents lose their jobs and incomes, the impact on children living in impoverished households must be measured. In this article, we assess the economic consequences of the pandemic on these children. Given that poorer families have a larger number of children than other families, the analysis first establishes the proportion of children living in monetary poor households, as defined by national standards, across developing countries. Then, using historical changes and trends of income distribution per country, the latest projections about economic decline due to the pandemic, and demographic information about the distribution of children by deciles, we estimate the expected increase in the number of children in monetary poor households in developing countries as of end of 2020 to be an additional 122-144 million and, at best, a moderate decline in these numbers by end of 2021.