ABSTRACT Background: Colonoscopy is a critical diagnostic and therapeutic procedure that is challenging to access in northern Canada. In part, this is due to frequent cancellations. We sought to understand the trends and reasons for colonoscopy cancellations in the Northwest Territories (NWT). Methods: A retrospective review of colonoscopy cancellations January, 2018 to May, 2019 was conducted at Stanton Territorial Hospital, NWT. Cancellation details and rationale were captured from the endoscopy cancellation logs. Thematic analysis was used to group cancellation reasons. Descriptive statistics were generated, and trends were analysed using run chart. Results: Of the scheduled colonoscopies, 368(28%) were cancelled during the 16 month period, and cancellations occurred, on average, 27 days after booking. Cancellation reasons were grouped into 15 themes, encompassing personal, social, geographic and health system factors. The most frequently cited theme was work/other commitments (69 respondents; 24%). Cancellations due to travel and accommodation issues occurred more frequently in the winter. Conclusion: Over one in four booked colonoscopies were cancelled and the reasons for cancellations were complex. Initiatives focusing on communication and support for patients with personal or occupational obligations could dramatically reduce cancellations. Ongoing collaborative efforts are needed to inform and optimise access to colonoscopy in this region.