To determine the influence of a surgical checklist (SC) on morbidities and compliance with safety measures. Before-and-after-intervention study. Three thousand two hundred eighty-six dogs: 1375 dogs pre-SC and 1911 post-SC. Completion of safety measures and occurrence of morbidity and/or mortality during hospitalization and up to death or 30-days postoperatively were recorded. Safety measures were more frequently completed post-SC, including oral confirmation of patient identity (467/1177 [40%] vs. 1911/1911 [100%]) and oral confirmation of surgical site (568/1175 [48%] vs. 1911/1911 [100%]). In addition, duration of anesthesia decreased from 241 to 232 min (t = 2.824; p = .005); a greater proportion of animals that were intended to receive antibiotics did so prior to incision (1142/1316 [86.8%] vs. 1656/1845 [89.8%] [χ2 = 6.70, p = .01]); and fewer dogs had unplanned return to the OR (32/1065 [3.0%], vs. 21/1472 [1.4%]) (χ2 = 7.52, p = .006). No difference in surgical site infection (adjusted odds ratio 1.02 [95%CI: 0.63-1.66]); morbidity, (adjusted odds ratio 1.00 [95%CI: 0.77-1.29]); or death within 30 days (adjusted odds ratio 1.15 [95%CI: 0.72-1.83]) was detected on multivariable logistic regression analysis. The checklist prevented one wrong-site surgery. Implementation of the checklist at our institution led to a decrease in anesthesia duration, increased administration of planned perioperative antibiotics before incision, increased completion of safety measures, and decreased unexpected return to the OR. Despite the lack of effect on morbidities, the use of SC is recommended to improve compliance with safety measures and potentially prevent rare catastrophic events.