Recent accounts of social difficulties in autism suggest that autistic and non-autistic individuals mutually misunderstand each other. This assumption aligns with findings that mixed-neurotype interactions are less efficient than same-neurotype interactions. However, it remains unclear whether different outcomes between mixed- and same-neurotype interactions are due to contact with a different neurotype or to inherently different communication styles, specific to each neurotype. A total of 134 adult participants were divided into three same-sex dyad types: 23 autistic dyads, 23 non-autistic dyads, and 21 mixed-neurotype dyads. Participants were unaware of their partner's neurotype. Dyads completed an online referential communication task where a "Director" guides a "Matcher" to rearrange abstract images, using both written (chat) and oral (microphone, no video) communication modes. Interaction outcome measures were task duration and verbosity of the Director. Across both communication modes, non-autistic dyads completed the task faster than autistic and mixed dyads, indicating that dyads with at least one autistic partner were generally slower. Notably, in mixed dyads, autistic Directors were more verbose than non-autistic Directors across both communication modes. These results, in conjunction with partners' unawareness of each other's neurotype, suggest that even in the absence of non-verbal cues neurotype mismatch triggers autistic adults to display different verbal behavior.