Resection is an important treatment modality for hepatocellular carcinoma (HCC) and intrahepatic cholangiocarcinoma (ICC). Anatomic resection is generally preferred for HCC. When anatomic resection is not feasible, prospective data have demonstrated an improved outcome among HCC patients who have a resection with wide versus narrow surgical margins. Similarly, among patients with ICC, R1 resection has been associated with worse outcomes. In addition, margin width may also impact risk of recurrence and survival. As such, provided adequate functional liver remnant remains, anatomic resection with wide margins is recommended for HCC and ICC.