Low back pain is a leading cause of disability worldwide and adults with chronic low back pain (≥12weeks) commonly experience sleep impairments (e.g., insomnia, sleep disturbance). This study examined the effects of non-pharmacological interventions on sleep in adults with chronic low back pain. Six databases (PubMed, CINAHL, SPORTDiscus, PsycINFO, EMBASE, CENTRAL) were searched from inception to 2 June 2021 for randomised controlled trials. Pairwise random-effect meta-analysis estimated standardised mean difference (Hedges’ g) at end-of-intervention follow-up. Nineteen studies (participants: 1348) were included. When compared to control, non-pharmacological interventions improved sleep (g [95%CI]: −0.33 [-0.56, −0.11], p = 0.004, small effect, I² = 59.3%; n = 879; studies: n = 13; GRADE: low). This small improvement in sleep was associated with a moderate reduction in pain intensity (−0.69 [-1.00, −0.38], p < 0.001, I² = 75.3%; n = 812; studies: n = 12; GRADE: very low) and no changes in back-related disability (−0.50 [-1.13, 0.14], p = 0.129, I² = 91.4%; n = 517; studies: n = 6; GRADE: low). Notably, all eligible studies reported interventions primarily aimed to reduce pain, although our search criteria were not limited to pain interventions. Key limitations were data paucity and high risk of bias. Future research should investigate sleep-based interventions (i.e., those purposely designed to improve sleep) using subjective and objective measures across a range of sleep domains (CRD42021275227).