Background Clinically significant delayed bleeding (CSDB) is the most common complication after colorectal endoscopic submucosal dissection (ESD). The Limoges Bleeding Score (LBS) was developed to identify high-risk patients. The efficacy of prophylactic clipping in reducing CSDB remains debated. This study assessed the effectiveness of complete clip closure in preventing CSDB after colorectal ESD. Methods A retrospective analysis of prospectively collected data from 10 centers (2019–2022) was conducted. ESD-treated epithelial colorectal lesions were included. Patients were categorized into closure and non-closure groups, and compared using propensity score matching (PSM) based on LBS factors (age > 75, lesion > 50 mm, American Society of Anesthesiologists III–IV, rectal location, anticoagulant/antiplatelet use). Subgroup analyses focused on anticoagulant use and high-risk patients (LBS 5–8). Environmental impact was estimated based on a representative sample. Results Among 3142 patients (1199 closure, 1943 non-closure), 216 (6.9 %) developed CSDB, with no difference between groups (closure: 7.2 % vs. non-closure: 6.9 %; P = 0.66). PSM analysis (944 matched cases) confirmed no statistically significant difference in CSDB (7.7 % vs. 5.7 %, respectively; P = 0.10). Subgroup analyses in patients on anticoagulants and at high risk showed no significant differences between the two groups (P = 0.39 and P = 0.73, respectively). Mean waste and carbon footprint was 283.2 g and 2.9 kg carbon dioxide equivalents, respectively, for single-use clips per closure (clip-to-lesion ratio: 0.8 clips/cm). Conclusions Prophylactic clipping did not significantly reduce CSDB following colorectal ESD, even in high-risk patients. Given its environmental impact and technical challenges, routine closure should be reconsidered.