This study examined the impact of a Collaborative Online International Learning (COIL) project on Thai Business English students' awareness of intercultural communication and English as a Lingua Franca (ELF), along with their communication challenges and strategies. Data were collected through pre-post rating-scale questionnaires, open-ended questions, semi-structured interviews, and reflective journals. The study found that while the virtual exchange did not significantly affect the students' overall intercultural and ELF awareness, it changed their attitudes toward ELF from negative to positive. The students reported increased confidence when communicating and presenting in English with a Thai accent and demonstrated a growing understanding of cultural differences in business communication. Despite this, the students identified several challenges, including language barriers, technical barriers, time zone differences, delayed responses, and non-compliance with established deadlines. To overcome these challenges, the students employed five effective communication strategies: developing cross-cultural communication skills, optimizing virtual meeting experiences, enhancing communication efficiency and collaboration, cultivating effective communication and relationship building, and practicing effective communication and conflict resolution. This study emphasizes the significance of virtual exchange for Business English students, as it enhances their intercultural communication skills and fosters acceptance of ELF, which is crucial for achieving success in today's globalized business landscape.