Objective: This study aimed to determine the rate of surgical site infection (SSI) in patients undergoing surgery for spinal metastases, and identify key risk factors for SSI among this patient group. Method: A retrospective case note review was undertaken in adult patients being treated at a single specialist centre for spinal surgery. Results: There were 152 patients identified for inclusion. Overall SSI rate was 11.2 per 100 patients (9.7 per 100 procedures). An increase in the risk of SSI was observed when surgery involved a greater number of vertebral levels (odds ratio 1.26, p=0.019) when controlling for primary spinal region. Controlling for the number of spinal levels, the odds of SSI increased by a factor of 5.6 (p=0.103) when the primary surgical region was thoracic, as opposed to cervical or lumbar. Conclusion: In conclusion, surgery associated with multiple vertebral levels for treatment of spinal metastases, particularly of the thoracic spine, is associated with increased risk of SSI.