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Introduction: The incidence of neuroendocrine tumors (NETs) of the colon has been increasing over the past decade, although little is known about associated prognostic factors. We sought to determine clinicopathologic factors influencing overall survival (OS).Methods: The National Cancer Database (1998-2002) was used to identify patients diagnosed with colonic NETs. 5-year OS was determined using the methods of Kaplan-Meier and a Cox proportional hazards model was used to assess clinicopathologic factors associated with OS. Results: A total of 2,188 patients were identified with a median age of 62.0 years and a 5 yr OS of 56.8% (median follow up = 4.2 years). The majority of colonic NETS were localized to the cecum (41.1%), followed by the sigmoid (16.3%), ascending colon (11.7%), rectosigmoid (11.6%), transverse (6.4%) and descending colon (1.7%). Distal colonic NETs (sigmoid or rectosigmoid) had the most favorable prognosis (69.1%) compared to proximal NETS located in the cecum (57.3%), ascending (39.3%), and transverse/descending colon (31.1%) (p<0.001). Distal colonic NETs were also more likely to present in younger patients with tumors that were of low histologic grade, ≤ 2 cm in size, and confined to the muscularis propria. On multivariate analysis, age (>75 years), high histologic grade, positive nodal ratio (≥0.3), tumor depth, and distant metastases were all independently associated with poorer OS. Conclusion: Distal colonic NETS are associated with improved 5-year OS compared to more proximally located tumors, likely due to earlier presentation of disease. Tumor location itself, however, was not independently associated with OS after adjusting for other clinicopathologic factors.