Objective: Smoking continues to be a major global cause of mortality and morbidity. Countries have increasingly adopted the use of images as warnings on cigarette packs. We aimed to investigate the likely differential impact of varied images and messages on sub-groups of the United Kingdom (UK) smoking population. Methods: Forty two images developed and approved by the European Union (EU) were viewed by participants in an online survey. Respondents indicated which images they felt would most effectively reduce rates of smoking. Socio-demographic data was sought from participating adults including age, sex, occupation, ethnicity and current smoking behaviour. There were 19,810 participants in the survey. Results: Three images, with graphic content, were found to consistently stand out as the most popular across all sub-groups. Smokers (as opposed to ex- and non-smokers) and men were found to vote for significantly fewer images, potentially indicating greater scepticism regarding the efficacy of images. Significant socio-demographic variations across a number of images were found suggesting that particular images and messages may have a differential impact on particular sub-groups. Conclusion: Images may vary significantly in their impact on different social sub-groups. Careful consideration is required when selecting which images to use. Attaching images targeting a sub-group to tobacco brands with that socio-demographic market may enhance the effectiveness of such warnings. (Contains 4 tables and 2 figures)