Across languages of the world /r/ is known for its variability. Recent literature incorporates sociolinguistic factors, such as bilingualism, in order to explain /r/ variation. The current study investigates to what extent /r/ is a marker of a bilingual’s dominant language. Specifically, the effects of several sociolinguistic and phonotactic factors on the production and perception of /r/ are investigated, such as the bilingual speaker’s linguistic background, the language spoken as well as syllable position and place of articulation. To this end a reading task is carried out with bilingual speakers from South Tyrol (Italy). The major languages spoken in this region are Tyrolean (German dialect) and Italian. The recorded reading data is subsequently used in a perception experiment to investigate whether South Tyrolean listeners can identify the dominant language of the speaker on the basis of the presence of /r/ and the /r/ variant. Results show that listeners can identify the dominant language of the bilingual speakers on the basis of /r/. Specifically, the more Italian dominant the sociolinguistic background of the speaker, the more /r/ is produced frontally and the more that speaker is perceived as Italian dominant.