Variations in the use and timeliness of chemotherapy were explored in 24,217 patients diagnosed with colon cancer and 8,170 patients diagnosed with rectal cancer in New Zealand between 1 January 2006 and 31 December 2016. The uptake and timeliness of chemotherapy was reported to improve over time. Overall, publicly funded chemotherapy was received by 27.8% of patients with colon cancer and 43.8% of patients with rectal cancer. Māori patients were among the three ethnic groups least likely to receive chemotherapy, coming second to Pacific patients and ahead of Asian patients. Initiation of chemotherapy within 10 weeks of diagnosis was more likely in patients who were younger, New Zealand European, resident in the Southern Cancer Network region and with metastatic disease. Age ≥80 years or a short life expectancy accounted for more than half of the patients with advanced colorectal cancer who did not receive chemotherapy.