PurposeBoth the arthroscopic Broström–Gould and Lasso‐loop stitch techniques are commonly used to treat chronic lateral ankle instability (CLAI). The purpose of this study is to introduce an arthroscopic one‐step outside‐in Broström–Gould (AOBG) technique and compare the mid‐term outcomes of the AOBG technique and Lasso‐loop stitch technique.MethodsAll CLAI patients who underwent arthroscopic lateral ankle stabilization surgery in our department from 2018 to 2019 were retrospectively enrolled. The patients were divided into two groups according to the surgical methods employed: the AOBG technique (Group A) and the Lasso‐loop technique (Group B). The visual analogue scale pain score, American Orthopaedic Foot and Ankle Society ankle hindfoot score, Tegner activity score and Karlsson–Peterson score were evaluated preoperatively and during the follow‐up from June to December 2022. The surgical duration, return to sports, sprain recurrence and surgical complications were also recorded and compared.ResultsA total of 74 patients (Group A, n = 42; Group B, n = 32) were included in this study with a mean follow‐up of 39 months. No statistically significant differences were observed in demographic parameters or follow‐up time between the two groups. Postoperative clinical scores indicated a significant improvement (all with p < 0.001) with no significant difference between the two groups (not significant [n.s.]). There was no significant difference in the surgical duration (46.1 vs. 49.7 min, n.s.), return to sports (92.9% vs. 93.8%, n.s.), or sprain recurrence (4.8% vs. 6.3%, n.s.). Only two cases in Group A reported knot irritation (4.8% vs. 0, n.s.), and one case in Group A experienced local skin numbness (0 vs. 3.1%, n.s.), with no significant difference.ConclusionBoth the AOBG and Lasso‐loop stitch techniques yielded comparable favourable mid‐term outcomes and return to sports with a low rate of surgical complications. Both procedures could be feasible strategies for CLAI patients.Level of EvidenceLevel III.