Western operationalisations of mindfulness employ informal mindfulness practices within stated mindfulness interventions, yet the practice of informal mindfulness remains elusive and lacks an understanding regarding its influence upon the cultivation of mindfulness. Hence, this study aims to investigate the influence of informal mindfulness practice upon the cultivation of mindfulness and perceived stress within non-clinical populations. In order to fulfil such a research aim, an intervention study was conducted involving 9 participants split across three sample groupings; each of which were exposed to varying levels of informal mindfulness practice. The intervention study totalled a duration of 12 days in which participants were subject to the practice of informal mindfulness, guided by teachings provided. A mixed-methods approach proved essential within the study’s data collection to gain a quantitative understanding of informal mindfulness practice upon the assessed variables; whilst also ensuring a qualitative exploration of participant experience and affect within the study. It was found that informal mindfulness practice proves influential within the cultivation of mindfulness, experience of associated beneficial effect and in the alleviation of perceived levels of stress, thus supporting the use of informal mindfulness practice within mindfulness interventions. Further conclusions are drawn regarding specifics of informal mindfulness practice, such as daily journaling, and the study concludes with recommendations for future research.