Online English language teaching can now be facilitated by communication technology, which allows easy access to interaction with native speakers. Nevertheless, this industry subscribes to an assumption that native speaker English teachers (NESTs) are the gold standard of language whereas the non-native speaker English teachers (NNESTs) are inferior educators (Walkinshaw & Duong, 2014). Rare research has provided evidence of the negotiation produced by NESTs versus NNESTs with EFL learners online and its impact on the learners' output. Thus, the current study narrows this empirical gap. Drawing upon a database of 30 five-minute interaction sessions between 30 teachers (15 NESTs and 15 NNESTs) and 30 basic level Vietnamese EFL adult learners, the study revealed similar negotiation of meaning functions as reported in previous research. However, the NESTs used more elaboration while the NNESTs used more confirmation checks, clarification requests, and reply clarification. Qualitative analysis further indicated that the NNESTs provided more productive support, encouraging the learners' output, than the NESTs did. This implies that although online voice interaction creates an environment for EFL learners to practice, language educators and teachers, regardless of status, should heed how to handle it so that online learners can benefit from both comprehensible input and opportunities for pushed output.