Lexical entrainment is a phenomenon in which people tend to re-use the words used by conversational partners (Brennan & Clark, 1996). It is explained as either an automatic reaction caused by priming (Pickering & Garrod, 2004), or a strategic behavior where two interlocutors achieve conceptual agreements for communicative purposes (Brennan & Clark, 1996). Past studies suggest that speakers tend to entrain more when interacting with listeners with lower language competence, such as computers (Branigan, Pickering, Pearson, McLean, & Brown, 2011), children (Cai, Sun, & Zhao, 2021), and non-native partners (Cai et al., 2021; Suffill, Kutasi, Pickering, & Branigan, 2021). However, few studies have explored how the features of speakers themselves determine the pattern of entrainment, and the studies that do exist suggest that speaker proficiency (as opposed to listener proficiency) may not affect entrainment behavior. In this study, we target bilingual groups and explore individual differences in lexical entrainment by looking at their entrainment behavior with picture matching and naming tasks. Over the course of two experiments, we investigate English entrainment in English-speaking bilinguals, as well as Mandarin entrainment in Mandarin-English bilinguals. Unlike the previous literature, our results suggest that a speaker’s language dominance/proficiency may have an effect on that speaker’s entrainment: bilinguals who are less dominant/proficient in English tend to entrain more in English, although the effect in Mandarin did not reach significance.