OBJECTIVE To examine the associations between family-reported social needs in primary care settings and pediatric health care use. METHODS Data were obtained for a sample of 56 253 children and youths (age 0-21 years) who received primary care at a large hospital-based pediatric institution between June 2018 and October 2019 to estimate a propensity score for the probability of being seen in a primary care clinic. Inverse probability weighted regression specifications were used to examine the associations between reported social needs and health care use. Families were asked about 4 social needs: housing, utilities, transportation, and food. Outcomes included the number of Emergency Department (ED), inpatient, social work, and well-child visits (only for those aged 0-2 years) in the 6 months before and after needs screening. RESULTS Overall, 12.0% of the families reported a general social need, with 28% of those needs identified as urgent. Food and transportation needs were most common. Patients with needs were more likely to have an ED or inpatient visit at 6 months prescreening and 6 months postscreening compared with those without needs. Among children aged <2 years, those with a social need were less likely to have completed a well-child visit at 6 months postscreening compared with those without a need. CONCLUSIONS Social needs are linked to less preventive care use and greater reliance on emergency care services. Understanding how to better assist families in need requires greater attention.