Adverse childhood experiences (ACEs) are preventable, potentially traumatic events in childhood, such as experiencing abuse or neglect, witnessing violence, or living in a household with substance use disorder, mental health problems, or instability from parental separation or incarceration. Adults who had ACEs have more harmful risk behaviors and worse health outcomes; the economic burden associated with these issues is uncertain. To estimate the economic burden of ACE-associated health conditions among US adults. In this economic evaluation, regression models of cross-sectional survey data from the 2019-2020 Behavioral Risk Factor Surveillance System (BRFSS) and previous studies were used to estimate ACE population-attributable fractions (PAFs) (ie, the fraction of total cases associated with a specific exposure) for selected health outcomes (anxiety, arthritis, asthma, cancer, chronic obstructive pulmonary disease, depression, diabetes, heart disease, kidney disease, stroke, and violence) and risk factors (heavy drinking, illicit drug use, overweight and obesity, and smoking) among the 2019 US adult population. Adverse childhood experience PAFs were used to calculate the proportion of total condition-specific medical spending and lost healthy life-years related to ACEs using Global Burden of Disease Study data. Data analysis was performed from September 10, 2021, to November 29, 2022. Adverse childhood experiences (age <18 years). Monetary valuation of ACE-associated morbidity and mortality using standard US value of statistical life methods and presented in terms of annual and lifetime per affected person and total population estimates at the national and state levels. A total of 820 673 adults, representing 255 million individuals, participated in the BRFSS in 2019 and 2020. An estimated 160 million of the total 255 million US adult population (63%) had 1 or more ACE, associated with an annual economic burden of $14.1 trillion ($183 billion in direct medical spending and $13.9 trillion in lost healthy life-years). This was $88 000 per affected adult annually and $2.4 million over their lifetimes. The lifetime economic burden per affected adult was lowest in North Dakota ($1.3 million) and highest in Arkansas ($4.3 million). Twenty-two percent of adults had 4 or more ACEs and comprised 58% of the total economic burden-the estimated per person lifetime economic burden for those adults was $4.0 million. In this cross-sectional analysis of the US adult population, the economic burden of ACE-related health conditions was substantial. The findings suggest that measuring the economic burden of ACEs can support decision-making about investing in strategies to improve population health.