Background: Major vascular involvement (IVC or portal vein) for intrahepatic cholangiocarcinoma (ICC) has traditionally been considered a contraindication to resection. We sought to define perioperative outcomes and survival of ICC patients undergoing hepatectomy with major vascular resection in a large international multi-institutional database. Methods: A total of 1087 ICC patients who underwent curative-intent hepatectomy between 1990 and 2016 were identified from 13 institutions. Multivariable logistic and cox regressions were used to determine the impact of major vascular resection on perioperative and survival outcomes. Results: Of 1087 patients who underwent resection, 128 (11.8%) also underwent major vascular resection (21 [16.4%] IVC resections, 98 [76.6%] PV resections, 9 [7.0%] combined resections). Despite more advanced disease, major vascular resection was not associated with the risk of any complication (OR = 0.68, 95%CI 0.32-1.45) or major complications (OR = 0.95, 95%CI 0.49-2.00). Post-operative mortality was also comparable between groups (OR = 1.05, 95%CI 0.32-3.47). In addition, median recurrence-free (14.0 vs 14.7 months, HR = 0.737, 95%CI 0.49-1.10) and overall (33.4 vs 40.2 months, HR = 0.71, 95%CI 0.359-1.40) survival were similar among patients who did and did not undergo major vascular resection (both P > 0.05). Conclusion: Among patients with ICC, major vascular resection was not associated with worse perioperative or oncologic outcomes. Concurrent major vascular resection should be considered in appropriately selected patients with ICC undergoing hepatectomy. © 2017 Wiley Periodicals, Inc.