Purpose: The purpose of the present study was to collect medical resource utilization data and costs in Ontario for the management of patients with relapsed or refractory chronic lymphocytic lymphoma (cll) who have undergone at least 1 treatment course and have been stratified by Rai staging. Methods: This retrospective longitudinal cohort study, conducted by chart review, analyzed anonymized patient records from two cancer centres in Ontario. Comprehensive records of 86 patients meeting the inclusion criteria were used to obtain resource utilization, which, multiplied by unit costs, were used to determine overall and mean costs. Descriptive statistics are presented for patient demographics, medical resource utilization, and costing data. Results: The total cost for the cohort was $2.2 million over a mean follow-up period of 4.7 years. The mean total cost per patient (regardless of follow-up) was $25,736. In terms of Rai staging, overall mean costs were highest for stage iv patients. Almost 50% of the total cost was attributable to cll treatments, among which fludarabine-based treatments had the highest utilization. Conclusions: For this Canadian cll cohort, medical resource utilization and costs were determined to be $2.2 million, with cll treatments accounting for about half the cost. Costs generally increased with Rai stage.