Health behavior incentive programs are increasingly common in Medicaid programs nationwide. Iowa's Healthy Behaviors Program (HBP) requires Medicaid expansion enrollees to complete an annual wellness exam and health risk assessment or pay monthly premiums to avoid disenrollment. The extent to which the program reduces the use of hospital-based care and lowers health care spending is unknown. Using data for 2012-17 from Medicaid and for 2014-17 from HBP, we evaluated changes in use and spending associated with HBP participation. Compared to nonparticipants, HBP participants were less likely to have an emergency department visit or be hospitalized (by 9.6 percentage points and 2.8 percentage points, respectively) but had higher total health care spending ($1,594). Meanwhile, Iowa's Medicaid expansion was associated with increased use and spending independent of HBP participation-that is, applying to both participants and nonparticipants. Overall, our findings suggest that the HBP was associated with substantial reductions in hospital-based care but increased health care spending.