Background: People who believe they have greater control over health and longevity are typically more likely to invest in their long-term health. Investigating individual differences in perceived control over risk, and exploring different determinants of health effort, may help to tailor the promotion of preventative health to more effectively encourage healthy behaviours. Method: We surveyed a nationally representative sample of 1,500 UK participants. We captured a range of socioeconomic variables and measured perceived control over 20 different causes of death. We also measured overall perceived uncontrollable mortality risk (PUMR), state-level optimism and the accuracy of estimations of avoidable deaths. Findings: We found individual differences in perceptions of control over specific causes of death based on age, gender and income. PUMR was predicted by socioeconomic variables expected to influence exposure to risk and resource availability. Overall, perceptions of control over specific causes of death did not predict self-reported health effort, whereas higher levels of PUMR did predict lower self-reported health effort. The strength of relationship between PUMR and health effort was not moderated by state-level optimism. Finally, age and education both positively predicted greater accuracy in assessing the prevalence of avoidable deaths.Conclusions: This study suggests that PUMR may capture people’s ‘general sense’ of mortality risk, influenced by both exposure to hazards and the availability of resources to avoid threats to health and longevity. Conversely, perceived control over specific risks may involve more deliberate, considered appraisals of risk. This general sense of risk is suggested to play a more notable role in determining health behaviours than specific assessments of control over risk. Further study is needed to investigate the degree to which PUMR accurately reflects objective measures of individual risk.