This study aims to characterize participation of neonatal intensive care unit (NICU) graduates in early intervention (EI). We used data from the National Early Intervention Longitudinal Study. We fit models of days from referral to Individualized Family Service Plan creation (plan time), days from referral to initiation of services (service time), and parent-reported effort to enroll their child with clinical and sociodemographic predictors. The sample of 1,188 NICU graduates had median birth weight 1,942 g, gestational age 33.4 weeks, and maternal age 27.4 years. Plan time was shorter for those with health insurance (2.5 weeks, p = 0.04) and living in high-providing states (3.3 weeks, p = 0.005). Service time was shorter for those with global delay (8 days, p = 0.02) and health insurance (11 days, p = 0.03) and longer for those with single parents (24 days, p = 0.009). Single parents and parents of children with higher birth weight, congenital problems, and non-White race reported greater effort finding services. Single parents and parents of female and higher birth weight infants reported greater effort initiating services. These findings document disparities in enrollment timing and service provision by disability types, single parenthood, and being of non-White race. Further elucidation of such disparities could lead to improved enrollment and access to prescribed services.