Formulaic sequences (FS) are frequently used by native speakers and have been found to help non-native speakers sound more fluent as well. We hypothesized that explicitly teaching FS to classroom ESL learners would increase the use of such language, which could further result in increased second language (L2) fluency. We report on a 5-week study where students in a control group (n = 8) heard authentic English and practiced speaking and listening using a task-based approach, while students in a treatment group (n = 11) did the same but also focused on noticing and using FS found in weekly topic transcripts. Measures of speech rate (syllables per minute) and mean length of run (number of syllables found in the longest stretch with no pauses) served as objective measures of fluency. Sixteen native-speaker judges assessed excerpts from pre- and posttests for subjective fluency. The number of syllables of FS (expressed as a ratio of the total number of syllables) was counted by two judges. Results found large effect sizes for group membership in all measures, with the treatment group increasing FS use and fluency to a large extent and statistically outperforming the control group on most measures. We conclude that explicitly teaching formulaic sequences may lead to increased use of such phrases and also increased fluency.