© 2020 Elsevier Inc. The way in which risk communication messages are framed can influence recipients' risk perceptions. Despite this, there is a limited understanding of how framing is responsible for influencing risk perception. One particularly important element may be whether a risk communication message is framed as a completed ‘risk assessment’ (specifying a magnitude of risk to the public as a function of the exposure level), or as a ‘hazard identification’ (a statement regarding whether an environmental agent could in principle cause detrimental health effects in humans, without addressing whether such effects may occur in practice). The current study aimed to investigate for the first time whether framing a risk communication message regarding ‘mobile phones and health’ as a hazard identification or as a risk assessment affects the reader's risk perception. Using an online survey, participants were separated into three groups and shown either an original press release from the International Agency for Research on Cancer regarding mobile phones and cancer (Group 1), or the press release with additional text modules intended to frame the press release as either a risk assessment (Group 2) or a hazard identification (Group 3). The experimental manipulation was successful in that framing the message as a hazard identification reduced the number of people that believed the press release was a risk assessment, whereas framing it as a risk assessment was not able to increase the number of people who thought that it was a risk assessment. However, no differences in risk perception were found between the groups. In an attempt to ascertain the reason for this lack of framing effect on the radiofrequency electromagnetic fields risk perception measures, it was found that pre-existing interpretations of risk and hazard strongly predicted risk perception, regardless of experimental group. Participants who believed that the International Agency for Research on Cancer conducted a hazard identification perceived lower risks and were less convinced that radiofrequency electromagnetic field exposure from mobile phones increases cancer risks. The results of the study demonstrate the importance of understanding the distinction between a hazard identification and a risk assessment, and suggest that radiofrequency electromagnetic field risk communication needs to develop means for empowering the public to differentiate between hazards and risks.