Typically, fewer than 0.5% of missing incidents result in an individual being found deceased. Whereas previous research has examined the features of missing–homicide, missing–suicide and some aspects of missing–accident cases, this study sought to provide the first reliable estimates of the number and proportion of fatalities by all causes of death, specifically: suicide, accident, homicide and natural causes. Using data obtained on 615 fatal disappearances via Freedom of Information returns from 22 English and Welsh police forces covering a two-year period, this article presents data on the relative probability of fatality by cause of death for adults and children and for males and females. Overall, fatal outcomes are, thankfully, rare, occurring once in every 358 missing incidents. Some 98% of fatalities involved adults; just over 80% involved males. The findings affirm suicide as the largest single cause of death accounting for three-quarters of female fatalities and four in every five male fatalities. Although homicide was the least probable cause of death among male missing persons, females faced a roughly similar chance of dying as a result of an accident or homicide. The research indicates that estimates of probability can be used to inform investigative decision-making and scenario development, offering important context to the overall likelihood of an individual facing a fatal outcome. Further research is needed to replicate these findings.