Background: Postoperative complications are common after colorectal surgery, and possibly related to the type of anaesthesia. We aimed to determine associations between the type of anaesthesia and complications after colorectal cancer surgery using Danish registries. Methods: Patients undergoing colorectal cancer surgery (2004–18) were identified in the Danish Colorectal Cancer Group Database. The cohort was enriched with the Danish Anaesthesia Database and Danish National Prescription Registry data linked by Danish Central Person Registration number. Patients were classified according to type of general anaesthesia: inhalation or TIVA. Confounders were adjusted by propensity score matching. The primary outcome was complications within 30 days postoperatively. Secondarily, we assessed specific medical and surgical complications. Results: We identified 22 179 individuals undergoing colorectal cancer surgery with accompanying anaesthesia data. Propensity score matching yielded 8722 individuals per group. After propensity score matching, postoperative complications were seen in 1933 (22.2%) patients undergoing inhalation anaesthesia and in 2199 (25.2%) undergoing TIVA (odds ratio [OR]=0.84; 95% confidence interval [CI], 0.79–0.91). Although no difference was observed for medical complications, 1369 (15.7%) undergoing inhalation anaesthesia had surgical complications compared with 1708 (19.6%) undergoing TIVA (OR=0.76; 95% CI, 0.71–0.83). Rates of wound dehiscence, anastomotic leak, ileus, wound abscess, intra-abdominal abscess, and sepsis were statistically significantly lower in the inhalation anaesthesia group. Conclusion: In this propensity score-matched registry study, use of inhalation anaesthesia was associated with fewer postoperative complications after colorectal cancer surgery than use of TIVA. Inhalation anaesthesia was associated with fewer complications related to wound healing and surgical infections.