The purpose of this study was (1) to examine the degree to which perceived burdensomeness mediates the relationship between pain severity and suicidal cognitions and (2) to determine whether this mediated relationship was moderated by pain acceptance. We predicted that high levels of pain acceptance would buffer relationships on both paths of the indirect effect. Two-hundred seven patients with chronic pain completed an anonymous self-report battery of measures, including the Chronic Pain Acceptance Questionnaire, the Interpersonal Needs Questionnaire, the Suicidal Cognitions Scale, and the pain severity subscale of the West Haven-Yale Multidimensional Pain Inventory. Conditional process models were examined with Mplus. Chronic pain acceptance significantly moderated both paths of the mediation model. Results from the conditional indirect effect model indicated that the indirect effect was significant for those with low (b = 2.50, P = .004) and medium (b = 0.99, P = .01) but not high (b = 0.08, P = .68) levels of pain acceptance and became progressively stronger as pain acceptance scores decreased. The nonlinear indirect effect became nonsignificant at acceptance scores 0.38 standard deviation above the mean-a clinically attainable treatment target. Higher acceptance mitigated the relationship between pain severity and perceived burdensomeness and the relationship between perceived burdensomeness and suicidal cognitions in this clinical sample of patients experiencing chronic pain. Findings indicate that any improvement in pain acceptance can be beneficial, and they provide clinicians with a clinical cut-point that might indicate lower vs higher suicide risk.