BACKGROUND: Massage is widely used for neck pain, but its effectiveness remains unclear. OBJECTIVES: To assess the benefits and harms of massage compared to placebo or sham, no treatment or exercise as an adjuvant to the same co-intervention for acute to chronic persisting neck pain in adults with or without radiculopathy, including whiplash-associated disorders and cervicogenic headache. SEARCH METHODS: We searched multiple databases (CENTRAL, MEDLINE, EMBASE, CINAHL, Index to Chiropractic Literature, trial registries) to 1 October 2023. SELECTION CRITERIA: We included randomised controlled trials (RCTs) comparing any type of massage with sham or placebo, no treatment or wait-list, or massage as an adjuvant treatment, in adults with acute, subacute or chronic neck pain. DATA COLLECTION AND ANALYSIS: We used the standard methodological procedures expected by Cochrane. We transformed outcomes to standardise the direction of the effect (a smaller score is better). We used a partially contextualised approach relative to identified thresholds to report the effect size as slight-small, moderate or large-substantive. MAIN RESULTS: We included 33 studies (1994 participants analysed). Selection (82%) and detection bias (94%) were common; multiple trials had unclear allocation concealment, utilised a placebo that may not be credible and did not test whether blinding to the placebo was effective. Massage was compared with placebo (n = 10) or no treatment (n = 8), or assessed as an adjuvant to the same co-treatment (n = 15). The trials studied adults aged 18 to 70 years, 70% female, with mean pain severity of 51.8 (standard deviation (SD) 14.1) on a visual analogue scale (0 to 100). Neck pain was subacute-chronic and classified as non-specific neck pain (85%, including n = 1 whiplash), radiculopathy (6%) or cervicogenic headache (9%). Trials were conducted in outpatient settings in Asia (n = 11), America (n = 5), Africa (n = 1), Europe (n = 12) and the Middle East (n = 4). Trials received research funding (15%) from research institutes. We report the main results for the comparison of massage versus placebo. Low-certainty evidence indicates that massage probably results in little to no difference in pain, function-disability and health-related quality of life when compared against a placebo for subacute-chronic neck pain at up to 12 weeks follow-up. It may slightly improve participant-reported treatment success. Subgroup analysis by dose showed a clinically important difference favouring a high dose (≥ 8 sessions over four weeks for ≥ 30 minutes duration). There is very low-certainty evidence for total adverse events. Data on patient satisfaction and serious adverse events were not available. Pain was a mean of 20.55 points with placebo and improved by 3.43 points with massage (95% confidence interval (CI) 8.16 better to 1.29 worse) on a 0 to 100 scale, where a lower score indicates less pain (8 studies, 403 participants; I AUTHORS' CONCLUSIONS: The contribution of massage to the management of neck pain remains uncertain given the predominance of low-certainty evidence in this field. For subacute and chronic neck pain (closest to 12 weeks follow-up), massage may result in a little or no difference in improving pain, function-disability, health-related quality of life and participant-reported treatment success when compared to a placebo. Inadequate reporting on adverse events precluded analysis. Focused planning for larger, adequately dosed, well-designed trials is needed.