The purpose of this study was to explore whether the co-speech gestures of interpreters align with those of a speaker during simultaneous interpreting. And if they do align, to investigate the functions that the aligned gestures serve and whether they provide information about the conceptual alignment of interpreters to a speaker. To achieve this, the gestures of three professional interpreters during a simulated remote simultaneous interpreting session were compared with those of the speaker using a mixed-methods approach. This consisted of qualitative micro-analyses and descriptive quantitative analyses of co-speech gestures. Gestural alignment with the speaker was found for all participants and across all functional dimensions, with representational gestures eliciting the highest percentage of alignment. The qualitative analysis of examples of aligned gestures with referential and interactive functions and of gestures used to organize the speech content metaphorically suggests that there was conceptual alignment of the interpreters with the speaker.