Objectives Studies examining perceptions of ‘modified risk tobacco product’ (MRTP) messages for e-cigarettes and smokeless tobacco have indicated consumers want statistics and quantification of harm reduction. However, limited research exists on reactions to quantitative MRTP messages.

Design We conducted 12 focus groups in the USA in 2019—6 focused on e-cigarette messages and 6 on snus messages. Eight groups were with current smokers (ages 21–66) and four with young adult (ages 18–25) non-smokers (n=57). Participants discussed messages stating that use of snus and vaping products have been estimated by scientists to be about 90% and 95% less harmful than smoking cigarettes, respectively.

Results Several participants agreed the messages strongly communicated that the products are less harmful than cigarettes, were attention getting and could be ‘convincing’. However, participants expressed scepticism about the source and accuracy of the stated figures, and some noted the claims could be misleading and attractive to young people. Comments also reflected some claim misunderstandings (eg, that e-cigarettes only pose a 5% chance of harm). Participants also agreed that stating e-cigarette risks ‘are unlikely to exceed 5% of cigarette smoking harms’ was confusing and less impactful than the ‘95% less harmful’ wording.

Conclusions Quantitative claims suggesting high levels of reduced risk when comparing e-cigarettes or smokeless tobacco/snus relative to cigarettes may be successful in gaining attention and being persuasive for some audiences, particularly, if from more credible sources. However, message developers, users and evaluators should be mindful of message limitations and aim to mitigate unintended consequences.