Children are at times asked by clinicians or researchers to rate their pain associated with their past, future, or hypothetical experiences. However, little consideration is typically given to the cognitive-developmental requirements of such pain reports. Consequently, these pain assessment tasks may exceed the abilities of some children, potentially resulting in biased or random responses. This could lead to the over- or under-treatment of children's pain. This review provides an overview of factors, and specifically the cognitive-developmental prerequisites, that may affect a child's ability to report on nonpresent pain states, such as past, future, or hypothetical pain experiences. Children's ability to report on past pains may be influenced by developmental (age, cognitive ability), contextual (mood state, language used by significant others), affective and pain-related factors. The ability to mentally construct and report on future painful experiences may be shaped by memory of past experiences, information provision and learning, contextual factors, knowledge about oneself, cognitive coping style, and cognitive development. Hypothetical pain reports are sometimes used in the development and validation of pain assessment scales, as a tool in assessing cognitive-developmental and social-developmental aspects of children's reports of pain, and for the purposes of training children to use self-report scales. Rating pain associated with hypothetical pain scenarios requires the ability to recognize pain in another person and depends on the child's experience with pain. Enhanced understanding of cognitive-developmental requirements of young children's pain reports could lead to improved understanding, assessment, and treatment of pediatric pain.