Objective To investigate death rates in schizophrenia and related psychoses. Design Data from two epidemiologically complete cohorts of patients presenting for the first time to mental health services in North Wales for whom there are at least 1, and up to 10-year follow-up data have been used to calculate survival rates and standardised death rates for schizophrenia and related psychoses. Setting The North Wales Asylum Denbigh (archived patient case notes) and the North West Wales District General Hospital psychiatric unit. Population Cohort 1: The North Wales Asylum Denbigh (archived patient case notes). Of 3168 patients admitted to the North Wales Asylum Denbigh 1875–1924, 1074 had a schizophrenic or related psychosis. Cohort 2: Patients admitted between 1994 and 2010 to the North West Wales District General Hospital psychiatric unit, of whom 355 had first admissions for schizophrenia or related psychoses. Results We found a 10-year survival probability of 75% in the historical cohort and a 90% survival probability in the contemporary cohort with a fourfold increase in standardised death rates in schizophrenia and related psychoses in both historical and contemporary periods. Suicide is the commonest cause of death in schizophrenia in the contemporary period (SMR 35), while tuberculosis was the commonest cause historically (SMR 9). In the contemporary data, deaths from cardiovascular causes arise in the elderly and deaths from suicide in the young. Conclusions Contemporary death rates in schizophrenia and related psychoses are high but there are particular hazards and windows of risk that enable interventions. The data point to possible interventions in the incident year of treatment that could give patients with schizophrenia a normal life expectancy.