Background: Surgery for TNM Stage II colon cancer is considered curative however approximately 20% of patients will have recurrence of their disease. A number of high risk pathological features guide the use of adjuvant chemotherapy. More recently the preoperative SIR has been consistently shown to have prognostic value but to date has not been utilised clinically as a high risk feature. The present study compared the influence of the SIR versus established high-risk clinical features on overall/cancer specific survival (OS/CSS). Methods: Patients in the West of Scotland undergoing curative resection for Stage II colon cancer from 2011-2015 were identified with survival updated until December 2018. Additional data was obtained from online records. Through uni/multivariate analysis (UVA/MVA) we compared the effect on survival of the SIR measured using the modified Glasgow Prognostic Score (mGPS), neutrophil-lymphocyte ratio (NLR) and lymphocyte-monocyte ratio (LMR) when entered individually into a multivariate model alongside established high-risk features. Results: 982 patients were identified having had a curative resection of Stage II colon cancer. Median follow up was 61 months and there were 307 deaths during follow up. For OS: emergency presentation, T stage, adjuvant chemotherapy, nodal harvest, margin involvement, mGPS, LMR, NLR (all p≤0.001) and EMVI (p < 0.05) were significant on UVA. On MVA: age (HR 1.51), T stage (HR 1.59), nodal harvest (HR 1.67), margin involvement (HR 1.94), adjuvant chemotherapy (HR 0.47), mGPS (HR 1.38), NLR (HR 1.35) and LMR (HR 1.50) remained significant (all p < 0.05). For CSS: age, emergency presentation, T stage, margin involvement, mGPS, NLR, LMR (all p < 0.001), nodal harvest and adjuvant chemotherapy (both p < 0.05) remained significant on UVA. On MVA emergency presentation (HR 1.88), T stage (HR 2.02), margin involvement (HR 2.98), adjuvant chemotherapy (HR 0.51) and mGPS (HR 1.34) remained significant (all p < 0.05). Conclusions: The present study suggests that the SIR is an independent predictor of worse OS/CSS in Stage II colon cancer and should be considered a high risk feature in future prospective studies.