BACKGROUND: Thoracic medial branch radiofrequency neurotomy (TMBRFN) is used to treat chronic thoracic facet joint pain, but research on its technique and effectiveness is still needed. The current International Pain and Spine Intervention Society Practice Guidelines do not describe a technique for TMBRFN. OBJECTIVES: Evaluate the effectiveness of TMBRFN in patients with thoracic facet joint pain. METHODS: Single-arm, retrospective cohort study of consecutive patients from two Canadian musculoskeletal pain management clinics who underwent first-time TMBRFN between 2016 and 2022. The primary outcome was the proportion of patients with ≥50 % reduction in numerical rating scale (NRS) pain score at 3-months post-procedure. Secondary outcomes included the proportion of patients who achieved a ≥17-point reduction on the Pain Disability Quality-Of-Life Questionnaire-Spine (PDQQ-S) at 3-months, as well as mean patient-reported percentage pain relief and duration of relief after a successful index TMBRFN in individuals who reported a return of their index symptoms. RESULTS: 18 consecutive patients (50.0 % male; mean age 60.9 ± 15.3 years; mean BMI 30.3 ± 6.9 kg/m) were analyzed. At 3 months post-procedure, 10 patients (55.6 % [95%CI 33.7-75.4]) reported ≥50 % NRS pain reduction and 9 (50.0 % [95%CI 29.0-71.0]) reported ≥17-point PDQQ-S reduction. Of the 10 patients with successful treatment responses, 4 had a return of symptoms after an average of 9.3 ± 2.2 months with a reported retrospective mean percentage pain relief of 70.0 ± 34.6 %. CONCLUSION: Within this cohort, approximately 60 % of patients experienced improvement in pain and disability at 3 months following TMBRFN. Among patients whose index symptoms returned after successful treatment, the average reported pain relief was 70 % for close to 9 months. Larger, prospective studies with long-term outcomes are needed to better elucidate the safety and effectiveness of TMBRFN.