A presumption of death occurs when a person is believed to be dead, despite the absence of direct proof of the person's death, such as the finding of remains attributable to that person. Such a presumption is typically made by an individual when a person has been missing for an extended period and in the absence of any evidence that person is still alive—or after a shorter period, but where the circumstances surrounding a person's disappearance overwhelmingly support the belief that the person is dead. The presumption becomes certainty if the person has not been located for a period of time that has exceeded their probable life span, such as in the case of Amelia Earhart or Jack the Ripper.

Paula Jean Welden was an American college student who disappeared while walking on Vermont's Long Trail hiking route. Local sheriffs were criticized for errors made in the investigation, which led to the creation of the Vermont State Police. Welden's fate remains unsolved, and was one of several unexplained disappearances in the same area at the time.