Abstract Describe how preterm infants experience residential mobility, or moving, before age 2 years. This retrospective cohort study included 9267 preterm infants followed in a mid-Atlantic urban and suburban primary care network. Multivariable regression modeling identified patient and community factors associated with residential mobility, defined by a change in Census Block Group. 2494 infants (27%) moved before age 2 years; 559 (6%) moved more than once.