The possible positive impact of aromas of plant essential oils is an area with a long history and one that is receiving increasing interest from modern science. Previous research has demonstrated beneficial effects of acute exposure on a range of variables. The current study set out to investigate for the first time whether extended exposure to the aroma of peppermint essential oil could provide benefits to healthy young adults. One hundred participants were randomly assigned to either wear a peppermint infused non-transdermal skin patch or a blank patch, for a period of six hours during which time they went about their normal daily routine. Cognitive and mood assessments were completed and a multivariate analysis of variance indicated a significant difference to exist between the two groups when all variables were analysed together. Further analyses on the individual variables revealed small to medium positive effects of peppermint aroma on aspects of memory and attention and feelings of subjective alertness. These findings add to a growing body of evidence that suggests aroma of peppermint essential oil may act as a positive and easy intervention delivering beneficial objective and subjective outcomes. The findings are discussed in terms of putative mechanisms that might underpin the effects with a focus on possible pharmacological influences.