IMPORTANCE: Effective, practical, nonpharmacologic therapies are needed to treat menopause-related insomnia symptoms in primary and women's specialty care settings. OBJECTIVE: To evaluate the efficacy of telephone-based cognitive behavioral therapy for insomnia (CBT-I) vs menopause education control (MEC). DESIGN, SETTING, AND PARTICIPANTS: A single-site, randomized clinical trial was conducted from September 1, 2013, to August 31, 2015, in western Washington State among 106 perimenopausal or postmenopausal women aged 40 to 65 years with moderate insomnia symptoms (Insomnia Severity Index [ISI] score, ≥12) and 2 or more daily hot flashes. Blinded assessments were conducted at baseline, 8, and 24 weeks postrandomization. An intent-to-treat analysis was conducted. INTERVENTIONS: Six CBT-I or MEC telephone sessions in 8 weeks. Participants submitted weekly electronic sleep diaries and received group-specific written educational materials. The CBT-I sessions included sleep restriction, stimulus control, sleep hygiene education, cognitive restructuring, and behavioral homework; MEC sessions provided information about menopause and women's health. MAIN OUTCOMES AND MEASURES: Primary outcome was scores on the ISI (score range, 0-28; scores ≥15 indicate moderate to severe insomnia). Secondary outcome was scores on the Pittsburgh Sleep Quality Index (score range, 0-21; higher scores indicate worse sleep quality). Additional outcomes included sleep and hot flash diary variables and hot flash interference. RESULTS: At 8 weeks, ISI scores had decreased 9.9 points among 53 women receiving CBT-I (mean [SD] age, 55.0 [3.5] years) and 4.7 points among 53 women receiving MEC (age, 54.7 [4.7] years), a mean between-group difference of 5.2 points (95% CI, -6.1 to -3.3; P < .001). Pittsburgh Sleep Quality Index scores decreased 4.0 points in women receiving CBT-I and 1.4 points in women receiving MEC, a mean between-group difference of 2.7 points (95% CI, -3.9 to -1.5; P < .001). Significant group differences were sustained at 24 weeks. At 8 and 24 weeks, 33 of 47 women (70%) and 37 of 44 (84%) in the CBT-I group, respectively, had ISI scores in the no-insomnia range compared with 10 of 41 (24%) and 16 of 37 (43%) in the MEC group, respectively. The CBT-I group also had greater improvements in diary-reported sleep latency, wake time, and sleep efficiency. There were no between-group differences in frequency of daily hot flashes, but hot flash interference was significantly decreased at 8 weeks for the CBT-I group (-15.7; 95% CI, -20.4 to -11.0) compared with the MEC group (-7.1; 95% CI, -14.6 to 0.4) (P = .03), differences that were maintained at 24 weeks for the CBT-I group (-22.8; 95% CI, -28.6 to -16.9) and MEC group (-11.6; 95% CI, -19.4 to -3.8) (P = .003). CONCLUSIONS AND RELEVANCE: Telephone-based CBT-I improved sleep in perimenopausal and postmenopausal women with insomnia and hot flashes. Results support further development and testing of centralized CBT-I programs for treating menopausal insomnia. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT01936441.