Background: Compared to the general population, individuals who have self-harmed have an increased risk of premature death, especially from unnatural or external causes of death, namely intentional self-harm, events of undetermined intent, and accidents.While risk factors for suicide following self-harm have often been investigated, rarely have those for accidents been studied.Our aim was to compare risk factors for suicide and accidents.Timing of death and risk profiles were used to identify discriminating and shared characteristics for suicide and different types of accidental death.Methods: A prospective cohort (N=30,202) from the Multicentre Study of Self-harm in England, 2000-2007, was followed up to the end of 2010 using national death registers.Risk factors for suicide (intentional self-harm and undetermined intent) and accidents (narcotic poisoning, non-narcotic poisoning, non-poisoning) were determined from an individuals last hospital presentation for self-harm and from their history during the study period using Cox models.Results: During follow up 1833 individuals died, 378 (20.6%) of these by suicide and 242 (13.2%) by accidents.At one year 0.66% (95% Cl 0.58, 0.76) had died by suicide and 0.32% (95% Cl 0.26, 0.39) by accidents.Independent predictors of both suicideand all three types of accidental deaths were: male gender, age 35+ years (except accidental narcotic poisoning deaths), socio-economic disadvantage (except non-poisoning accidental deaths), repeated self-harm, and psychiatric treatment history.Factors differentiating risk of suicide from accidental death were last method of self-harm (2-3-fold increased risks for other self-injury v.self-poisoning) and mental health problems.Specific risk factors for death from accidental narcotic poisoning were recreational/illicit drug problems at the last presentation for self-harm; and for accidental non-narcotic poisoning were alcohol involvement with self-harm.Conclusion: The similarity of risk factors for suicide and accidents indicates common experiences of socio-economic disadvantage, life problems and psychopathology resulting in a variety of self-destructive behaviour.Of the three accidental death groups, risk factors for non-narcotic poisoning were most similar to suicide.Differences between suicides and accidental non-narcotic poisoning deaths appeared to be partly related to the criteria that coroners use in making verdicts.Our findings support the idea of a continuum of premature death and the commonality of risk factors.