Abstract: Background: Use of complementary and integrative health (CIH) therapies has increased over the past two decades. Accumulating evidence supports the effectiveness of CIH therapies for a range of health outcomes and an association between CIH therapy use and reduced use of opioid therapy. Objective: To describe differences in the use of evidence-based CIH therapies among individuals with chronic pain on long-term opioid therapy (LTOT) by sociodemographic and clinical characteristics. Design: This was an observational study using a national retrospective cohort of patients developed from Veterans Affairs (VA) electronic health record data. Sample: The sample comprised 281, 903 patients receiving LTOT upon cohort entry between July 1, 2017, and December 31, 2021, with a health care encounter in one of 54 VA medical centers. Main Measures: CIH therapy use was defined as chart-documented use of any of eight priority CIH therapies or chiropractic care in the year prior to cohort entry. LTOT was defined as having a prescribed opioid analgesic for ≥90 consecutive days, allowing ≤30 days between fills. Sociodemographic and clinical characteristic variables were assessed as covariates of CIH therapy use. Key Results: Among the full cohort, the CIH therapy use rate was 9.5%. Use increased with each cohort entry year relative to 2017. In a multivariable model, variables associated with greater odds of CIH therapy use included being female, having a musculoskeletal pain condition, obesity, opioid use disorder, anxiety, depression, post-traumatic stress disorder, and receiving services in a flagship site. Lower odds of use were associated with being older, unmarried, prescribed higher opioid doses, smoking, and rural residence. Conclusions: CIH therapy use has increased over time, consistent with national trends; however, differential patterns of exposure suggest the need to explore pathways to use. These may elucidate opportunities to broaden access to these evidence-based therapies for patients with chronic pain.