As part of the Thriving Communities, Thriving State project, this issue brief examines trends in domestic migration for Indiana's urban, mid-sized, and rural counties. Comparing Indiana’s domestic migration across counties suggests that many counties in Indiana are only growing because individuals are relocating from other parts of the state. These domestic migration patterns are not sustainable for long-term population growth—they highlight that Indiana counties rely on one another’s residents for population growth rather than residents of other states. The data presented here underscore several key trends in county-level migration in Indiana: • Mid-sized Indiana counties provide the greatest source of growth in Indiana due to net domestic migration. This growth is mostly from: o Individuals moving from Urban Indiana to Midsized counties surrounding Indianapolis, and o Individuals moving from Rural to the other Mid-sized Indiana counties. • Indiana communities of all types have undergone a net loss in domestic migration to other U.S. states. o Most of those states are in the Sun Belt, are experiencing some of the largest population growth nationally, and are projected to continue that trend. o Individuals who move to other states from Indiana tend to move to metropolitan areas. o Urban counties in Indiana had the greatest net losses to other states. • Neighboring counties are sources of growth for some counties. o Rural populations may be attracted to more urban locations. o Domestic migration to border counties also exists for state-to-state migration, especially for Rural and Mid-sized counties. Overall, Indiana risks increasingly smaller population growth in all regions of the state due to multiple factors, but mostly related to losses in net domestic migration.