Purpose. The present survey examined the beliefs of different occupational groups (police officers, social workers, teachers) and members of the general public about (i) cues to deception in young children (5- to 6-year-olds), adolescents (14- to 15-year-olds) and adults, and (ii) the underlying processes (emotions, cognitive load and attempted verbal and behavioural control), which may explain why cues to deceit do occur. Method. Two hundred and six participants completed a ‘cues to deception’ and ‘processes underlying deception’ questionnaire for three different age groups (young children, adolescents and adults). Results and discussion. The survey revealed that participants believed that liars are nervous, have difficulties in formulating their lies and do not fully endorse their lies. In general, participants associated more cues with deception than seems justified on the basis of deception literature. Participants generally associated the same cues to deceit for all three age groups but, when differences between age groups did emerge, this was most likely to be amongst teachers. Although participants believed that adults control their speech and behaviour more when they lie than adolescents and young children do, this did not result in participants believing that adults exhibit fewer cues to deceit. No major occupational differences emerged, although out of the four participating groups, teachers were most likely to associate cues with deception in young children.