Daniella Medeiros Cavalcanti and colleagues estimate that funding cuts to the United States Agency for International Development (USAID) could lead to more than 14 million additional deaths worldwide by 2030, including 4.5 million children under 5. However, this model likely underestimates the true impact because it does not take into account three key factors that could increase the number of casualties. USAID-supported programs were associated with a 15 percent decrease in all-cause deaths and up to a 32 percent decrease in under-five deaths. A reduction in funding therefore poses a significant risk to global health and increases the likelihood of increased mortality in vulnerable populations. USAID plays an important role in providing foreign aid that contributes to improving health care and disease prevention in developing countries. Cuts to the agency's budget could threaten public health advances and increase the human cost globally.