OBJECTIVE:To evaluate long-term treatment efficacy and safety of one-time telemedicine consultations for nonacute headaches. METHODS:We randomized, allocated, and consulted nonacute headache patients via telemedicine (n = 200) or in a traditional manner (n = 202) in a noninferiority trial. Efficacy endpoints, assessed by questionnaires at 3 and 12 months, included change from baseline in Headache Impact Test–6 (HIT-6) (primary endpoint) and pain intensity (visual analogue scale VAS) (secondary endpoint). The primary safety endpoint, assessed via patient records, was presence of secondary headache within 12 months after consultation. RESULTS:We found no differences between telemedicine and traditional consultations in HIT-6 (p = 0.84) or VAS (p = 0.64) over 3 periods. The absolute difference in HIT-6 from baseline was 0.3 (95% confidence interval CI −1.26 to 1.82, p = 0.72) at 3 months and 0.2 (95% CI −1.98 to 1.58, p = 0.83) at 12 months. The absolute change in VAS was 0.4 (95% CI −0.93 to 0.22, p = 0.23) after 3 months and 0.3 (95% CI −0.94 to 0.29, p = 0.30) at 12 months. We found one secondary headache in each group at 12 months. The estimated number of consultations needed to miss one secondary headache with the use of telemedicine was 20,200. CONCLUSION:Telemedicine consultation for nonacute headache is as efficient and safe as a traditional consultation. CLINICALTRIALS.GOV IDENTIFIER:NCT02270177. CLASSIFICATION OF EVIDENCE:This study provides Class III evidence that a one-time telemedicine consultation for nonacute headache is noninferior to a one-time traditional consultation regarding long-term treatment outcome and safety.