Total health expenditures under a Medicare for All plan that provides comprehensive coverage and long-term care benefits would be $3.89 trillion in 2019 (assuming such a plan was in place for all of the year), or a 1.8 percent increase relative to expenditures under current law. This estimate accounts for a variety of factors including increased demand for health services, changes in payment and prices, and lower administrative costs. We also include a supply constraint that results in unmet demand equal to 50 percent of the new demand. If there were no supply constraint, we estimate that total health expenditures would increase by 9.8 percent to $4.20 trillion.