Purpose. Primary care physicians (PCP) experience high rates of professional burnout. These symptoms may be magnified in underserved populations. This study explores relationships between clinic capacity to address patients' social needs (SN) and PCP burnout. Methods. We conducted a cross-sectional survey of PCPs from three delivery systems in San Francisco. Surveys included three components of burnout, measured by the Maslach Burnout Inventory (MBI) and a four-item instrument exploring attitudes, confidence, individual skills and organizational capacity to address patients' SN. Results. Provider perception of higher clinic capacity to address patients' SN was the strongest independent predictor of lower burnout. Providers who perceived high clinic capacity and resources to address SN reported significantly greater professional efficacy (p <.01), lower emotional exhaustion (p <.05), and lower cynicism (p <.05). Conclusions. Provider perceptions of greater clinic capacity to address SN are significantly associated with lower burnout. Devoting organizational resources to address SN may reduce PCP burnout.