Background: Being diagnosed with cancer can be overwhelming, with many physical and emotional challenges. As needs of survivors shift from disease management to recovery, the adjustment is often not seamless. Ideally, a health care system is integrated and responsive to the needs of survivors, however, when cancer treatment is complete, they often face lingering concerns. Limited patient-reported data were available in Canada on experiences and barriers survivors face posttreatment. Aim: The Experiences of Cancer Patients in Transition study is the first national survey gathering data from cancer survivors in Canada as they transition from cancer care to the broader health care system. Methods: A survey was developed in consultation with patients/survivors, health care providers and researchers to address experiences related to physical, emotional, informational and practical needs. Ethics approvals were obtained and 10 provinces participated. Cancer survivors expected to have completed treatment within 1-3 years were identified from provincial cancer registries. Included were those aged 30+ at diagnosis of nonmetastatic breast, colorectal, prostate, melanoma or hematologic cancer; or aged 15-29 at diagnosis of any nonmetastatic cancer or metastatic testicular cancer. Despite the intention of the sampling, the final sample included some survivors diagnosed with a site other than the target sites, and some whose time since treatment was outside 1-3 years. All respondents are included in this analysis. Results are not weighted to represent the true distribution of cancer survivors. Results: From a total survey population of 40,790 Canadian cancer survivors, 33% completed the survey. The respondents were 48% male, 51% female; 2.5% were under 30 years old, 60% were 65+. 68% of respondents reported challenging periods posttreatment, with 48% of these saying that the first 6 months to 1 year were most challenging. Cancer survivors continued to live with side-effects: 87% reported physical challenges; 78% reported emotional challenges; 45% reported practical challenges. The most prevalent concerns were fatigue (68%), anxiety about cancer returning (68%) and returning to work/school (23%). Less than half of those with emotional or practical concerns received useful information (42% and 46%, respectively). 42% of respondents could not get help to address their most difficult concern. Of those who could get help, 10.7% waited a year or more. Conclusion: The results provide insight into the nature of challenges cancer survivors face, as well as needed supports and barriers faced in accessing them. There is a clear need for health systems to ensure a seamless patient experience throughout the cancer journey, for instance, through development and adoption of resources to help health care providers and their patients identify and address challenges from diagnosis through to survivorship.