Abstract Background This study assessed the feasibility and outcomes of combined colorectal and hepatic resection as the first step of two-stage hepatectomy in patients with bilobar synchronous colorectal liver metastases. Methods All patients with bilobar synchronous colorectal liver metastases who were considered for two-stage hepatectomy, combining resection of the primary tumour with the first stage of hepatectomy, between 2000 and 2008 were selected from a prospectively collected database at two institutions. Data were analysed retrospectively on an intention-to-treat basis. Results Thirty-three patients were studied. Twenty patients received neoadjuvant chemotherapy. Combined colorectal resection and clearance of left-sided liver metastases was the first-stage procedure in all but one patient, in whom right clearance was performed. In 17 patients right portal vein ligation was undertaken at the same time. No patient died. Two patients had anastomotic leakage. Interval chemotherapy was given to 25 patients, five of whom also had percutaneous portal vein embolization. Twenty-five patients had the second-stage hepatectomy, but not eight patients with disease progression. There was one postoperative death after the second stage, and eight patients experienced morbidity. Median follow-up from the first stage was 28·7 months. Overall and disease-free survival rates for patients who completed the procedure were 80 and 44 per cent respectively at 3 years, and 48 and 22 per cent at 5 years. Conclusion In patients with bilobar synchronous colorectal liver metastases who are candidates for two-stage hepatectomy, combined resection of the primary tumour and first-stage hepatectomy reduces the number of procedures, optimizes chemotherapy administration and may improve outcome.