-  Aarhus University [NORA names: AU Aarhus University; University; Denmark; Europe, EU; Nordic; OECD]
-  Central Denmark Region [NORA names: Central Denmark Region; Hospital; Denmark; Europe, EU; Nordic; OECD]
-  Aarhus University Hospital [NORA names: Central Denmark Region; Hospital; Denmark; Europe, EU; Nordic; OECD]
-  Danish Cancer Society Research Center [NORA names: DCRC Danish Cancer Society Research Center; Specialized Research; Denmark; Europe, EU; Nordic; OECD]
-  Morneau Shepell [NORA names: Canada; America, North; OECD]
-  Regional Hospital West Jutland [NORA names: Central Denmark Region; Hospital; Denmark; Europe, EU; Nordic; OECD]
Purpose: Work-related issues have become increasingly relevant for colorectal cancer (CRC) patients, since the cancer is detected at an earlier age due to screening. The aim was to evaluate work participation up to 10 years after colon or rectal cancer diagnosis compared between diagnosis and to a matched cancer-free population. Methods: In this national register-based cohort study, all first-time CRC patients in the period 2000–2015 with no previous cancer, between 20 and 60 years, were identified in the Danish Cancer Registry. A control group with no previous cancer was matched on gender, age, education, and income. For each year a mean Work Participation Score (WPS) was calculated (a percentage of weeks working) for individuals part of the labour market. Results: A total of 5625 colon cancer patients and 3856 rectal cancer patients and 25,341 and 17,256 matched controls were included in the study, respectively. The WPS increased for colon cancer patients from 45.69% after 1 year to 83.94% after 4 years, while rectal cancer patients had a score of 38.07% after 1 year and 80.07% after 4 years. The WPS was lower for cancer patients compared with controls, but the difference decreased after 4 years. Conclusion: CRC patients had a lower work participation up to 10 years after diagnosis compared with controls, while rectal cancer patients had a lower participation the first 7 years after diagnosis compared with colon cancer patients. Implications for cancer survivors: Work-related issues should be considered in the early stage of rehabilitation to increase work participation and thereby improve quality of life.