Objective To determine the extent of medical and non-medical out-of-pocket expenses (OOPE) among regional/rural and outer metropolitan Western Australian patients diagnosed with cancer, and the factors associated with higher costs. Methods Cross-sectional data were collected from adult patients living in four regional/rural areas and two outer metropolitan regions in Western Australia who had been diagnosed with breast, prostate, colorectal or lung cancer. Consenting participants were mailed demographic and financial questionnaires, and requested to report all OOPE related to their cancer treatment. Results The median total OOPE reported by 308 regional/rural participants and 119 outer metropolitan participants were A$1518 (interquartile range (IQR): A$581-A$3769) and A$2855 (IQR: A$958-A$7142) respectively. Participants most likely to experience higher total OOPE were younger than 65 years of age, male, resided in the outer metropolitan area, worked prior to diagnosis, had private health insurance, were in a relationship, and underwent surgery. Multivariate analysis of regional/rural participants revealed that receiving care at a rural cancer centre was associated with significantly lower non-medical OOPE (estimated mean A$805, 95% confidence interval (CI): A$735-A$875, P=0.038; compared with other rural participants (A$1347, 95% CI: A$743-A$1951, P<0.001)). Conclusion The cancer patients who participated in this study experienced variation in OOPE, with outer metropolitan participants reporting higher OOPE compared with their regional/rural counterparts. There is a need for cost transparency and access to care close to home, so that patients can make informed choices about where to receive their care. What is known about the topic? In recent years, OOPE for health care in general and cancer in particular have been widely debated by consumers and not-for-profit organisations; the topic has attracted much political attention because it affects both equity and access to care and has wider financial implications for the community. Research studies and reports from both consumer organisations and a Ministerial Advisory Committee found that cancer patients can face exorbitant out-of-pocket costs, and that individuals with private health insurance and those with prostate and breast cancer reported higher costs. In Western Australia, a cancer centre providing comprehensive cancer care was established in the second most populous region to ameliorate the high costs for travel and accommodation that regional cancer patients are known to experience. What does this paper add? This study is unique because it collected detailed cost information from patients and reports on the OOPE of regional/rural and outer metropolitan Western Australian patients receiving care for one of the four most common cancers; it therefore offers novel insight into the experiences of these groups. This study demonstrates that outer metropolitan cancer patients are experiencing much higher OOPE compared with regional/rural cancer patients. Additionally, regional/rural study participants who accessed a Regional Cancer Centre experienced significantly lower non-medical OOPE, compared with regional/rural study participants receiving care elsewhere. What are the implications for practitioners? First, there is a need for improved communication of OOPE to minimise costs to the patient, for example, by facilitating access to local cancer care. Health service providers and insurance companies can improve cost transparency for cancer patients by making this information more readily available, allowing patients to make informed financial choices about where to seek care. Second, the needs of working patients deserve specific attention. These patients face significant work uncertainty and additional distress following a cancer diagnosis.