Filled pauses are well known for their speaker specificity, yet cross-linguistic research has also shown language-specific trends in their distribution and phonetic quality. To examine the extent to which speakers acquire filled pauses as language- or speaker-specific phenomena, this study investigates the use of filled pauses in the context of adult simultaneous bilinguals. Making use of both distributional and acoustic data, this study analyzed UH, consisting of only a vowel component, and UM, with a vowel followed by [m], in the speech of 15 female speakers who were simultaneously bilingual in French and German. Speakers were found to use UM more frequently in German than in French, but only German-dominant speakers had a preference for UM in German. Formant and durational analyses showed that while speakers maintained distinct vowel qualities in their filled pauses in different languages, filled pauses in their weaker language exhibited a shift towards those in their dominant language. These results suggest that, despite high levels of variability between speakers, there is a significant role for language in the acquisition of filled pauses in simultaneous bilingual speakers, which is further shaped by the linguistic environment they grow up in.