Palliative chemotherapy is routinely given to patients diagnosed with locally advanced or metastatic oesophagogastric (O-G) cancer. We examine which patients with O-G cancer in England receive palliative chemotherapy, and identify factors associated with treatment completion. A prospective population-based observational study. All English National Health Service (NHS) trusts diagnosing patients with O-G cancer. Data were prospectively collected on patients diagnosed with invasive epithelial cancer of the oesophagus or stomach between 1 October 2007 and 30 June 2009 in English NHS hospitals, and those who had palliative treatment intent. We calculated the proportion of patients with different characteristics (eg, age, sex, stage at diagnosis, performance status) starting palliative chemotherapy. Multiple logistic regression was used to identify characteristics associated with non-completion of chemotherapy. There were 9768 patients in the study whose treatment intent was palliative. Among these, 2313 (24%) received palliative chemotherapy. It was received by 51% of patients aged under 55 years but only 9% of patients aged 75 years or over. Overall, 917 patients (53%) completed their treatment among the 1741 patients for whom information on treatment completion was recorded. Treatment completion ranged from 50-60% for patients with good performance status but was under 35% for patients aged 55 years or older with poor performance status. Treatment completion was not associated with site of cancer, pretreatment stage, sex, comorbidities or histology. Completion rates of palliative chemotherapy in patients with O-G cancer are low and elderly patients with poor performance status are very unlikely to complete a palliative chemotherapy treatment. Clinicians and patients should consider this information when balancing potential (survival) benefits, toxicity of treatment and its effect on quality of life.