Mindfulness has received increased attention recently in educational contexts as a tool helping students mitigate negative emotions, enhance resilience, reduce classroom anxiety, and improve academic performance. Although interventions that teach mindfulness principles have flourished in elementary school and university contexts, limited research has investigated the effects of interventions in educational contexts for English language learning. This study investigates student perceptions of the effectiveness of mindfulness interventions in an intensive English program for non-matriculated university students where teachers taught a 65-minute mindfulness lesson once a week for 13 weeks in addition to their normal English language curriculum. Six teachers and 107 English language learners participated. Teachers were given the flexibility to decide how best to incorporate the mindfulness interventions into their lessons. Survey and focus group data were collected. The qualitative comments were analyzed following a phenomenological approach to understand how students perceived their individual learning experiences. Students' overall reaction to the mindfulness interventions was positive; they highlighted benefits to both their emotional toolbox and their classroom experience. Implications of this research incorporating mindfulness instruction into the ESL classroom are also included.