Background: Adjuvant chemotherapy (AC) for CC has been shown to increase survival in randomized trials. Analysis of time from curative surgery to AC (TTAC) has demonstrated diminished survival with increasing TTAC. Few studies have examined the reasons underlying delays in TTAC. Methods: Data was extracted from individual medical records of 1159 patients with CC who initiated AC at six large academic centers in Ontario between 2005-2012, including patient demographics, disease characteristics, treatment, readmissions, length of hospital stay, post-operative complications and time intervals between each step from surgery to AC. Patients were categorized into three Groups: (I) postoperative surgical /medical complications, (II) oncologist or patient-initiated delay, (III) no delays. Groups were compared using X² test and one-way analysis of variance. A multivariable logistic regression model was used to determine factors associated with TTAC > 8 weeks. Results: In this 1159 patient cohort, 54% were male, with 48% under 65 and 19% over 74 years of age. There were 21%, 18% and 60% in Groups I, II, III respectively. TTAC in the 3 Groups was (I) 9.9±2.9 weeks, (II) 10.2±3.6 weeks, (III) 8.8±2.7 weeks (P < 0.01). In multivariate analysis, advanced age, postoperative complications, oncologist- or patient-initiated delays and need for central line placement were significant predictors for TTAC > 8 weeks. In group III (n = 615), age (65-74 years) (OR = 1.54; 95% CI, 1.05-2.26) and central line (OR = 2.01; 95% CI, 1.27-3.17) were significant factors for TTAC > 8 weeks. In group III, 59% had TTAC > 8 weeks. In the overall cohort, 65% had TTAC > 8 weeks even though 92% were deemed fit for chemotherapy at the original consultation. Conclusions: In major academic centers in Ontario, the majority of patients receive AC more than 8 weeks after surgery, even though most patients had no identifiable medical or surgical reasons for delay. This is likely due to health-system factors such as delay in referrals, consultations, central line placement and chemotherapy bookings. Local and regional quality improvement initiatives are needed to improve health-system delays and decrease TTAC.