Background Trigeminal neuralgia (TN) is an excruciating unilateral facial pain, which negatively affects patient's quality of life. Historically, it has been difficult to compare treatment efficacy due to the lack of standardized outcomes. In addition, patients' perspective has seldomly been acknowledged. The aim of this study was to reach consensus on what outcomes of treatment are important to different TN stakeholders (patients, clinicians and researchers), to identify the TN Core Outcome Set (TRINCOS). Methods A list of outcomes identified through a systematic review and focus group work was used to develop the survey questionnaire. A three-round Delphi was conducted. Participants were asked to score the outcomes on scale from 1 to 9 (1-3 not important;4-6 important but not critical;7-9 critical). Outcomes scored as critical by >= 70% and not important by <15% were retained, and those for which no consensus was reached were discussed at a consensus meeting. Results Of the 70 participants who completed the Delphi, 26 were patients, 38 were clinicians and six were researchers. Of the 40 outcomes presented, 17 were scored as critical and no consensus was met for 23 outcomes. Agreement was reached during a consensus meeting on 10 outcomes across six domains (pain, side effects, social impact, quality of life, global improvement, and satisfaction with treatment). Conclusion Implementation of TRINCOS in future clinical trials will improve homogeneity of studies' results, reduce the redundancy in the outcome assessment and effectively allow comparison of different treatments to better inform researchers, clinicians and most importantly patients, about the efficacy of the different treatments. Significance Implementation of a 10-item core outcome set in trigeminal neuralgia will improve comparability between studies allowing patients to have faster access to better treatments.