Purpose To describe the prevalence of fatigue in adults with colorectal cancer (CRC). Additionally, to explore the associations and correlations between fatigue and sociodemographic and clinical characteristics. Methods Patients with CRC at various phases of the disease were evaluated for fatigue using the Brief Fatigue Inventory (BFI), independence in activities of daily living using the Barthel index, perception of pain using the Visual Analogue Scale (VAS), and performance status using the Eastern Cooperative Oncology Group criteria in a Chilean public hospital. Descriptive analyses were used to describe the variables. Chi-square and Spearman tests were utilized to evaluate associations between fatigue and other variables. Results Among 241 patients participate (mean age 68.9 ± 12.2 years) and colon cancer was most common (66.4%). Fatigue was present in all disease phases, with moderate fatigue most prevalent (49.3%), followed by mild (24.2%) and severe (13.6%). Newly diagnosed patients had a higher proportion of severe fatigue (p = 0.04). Women experienced more moderate fatigue than men (p < 0.05). Patients with over three comorbidities and severe pain had higher severe fatigue (p < 0.05). Mood disorders were linked to more severe fatigue, while their absence was related to milder fatigue (p = 0.02). Musculoskeletal disorders correlated with moderate fatigue, while their absence correlated with mild fatigue (p < 0.01). Small positive correlations existed between fatigue and age (Rho = 0.15) and pain (Rho = 0.23) (p < 0.05). Conclusion Cancer-related fatigue (CRF) is highly prevalent in individuals with CRC and can be present throughout all phases of the disease. Early screening and management are recommended, prior to surgical treatment.