Previous studies have found that talkers converge or diverge in phonetic form during a single conversational session or as a result of long-term exposure to a particular linguistic environment. In the current study, five pairs of previously unacquainted male roommates were recorded at four time intervals during the academic year. Phonetic convergence over time was assessed using a perceptual similarity test and measures of vowel spectra. There were distinct patterns of phonetic convergence during the academic year across roommate pairs, and perceptual detection of convergence varied for different linguistic items. In addition, phonetic convergence correlated moderately with roommates' self-reported closeness. These findings suggest that phonetic convergence in college roommates is variable and moderately related to the strength of a relationship.