The global prevalence of English as a lingua franca (ELF) across diverse linguacultural communities within the three circles invites an in-depth analysis of its phonological and lexicogrammatical features, especially among non-native English speakers. This qualitative study investigated these features among 30 Thai students from English and nonEnglish programs, emphasizing natural occurrences in academic settings. Participants were directed to record audio and video during collaborative activities with peers and lecturers inside and outside the classroom. Through Conversation Analysis, findings revealed a significant divergence in the phonological and lexicogrammatical features of ELF participants compared to speakers of standard British English (BrE) and American English (AmE). Specifically, nonstandard lexicogrammatical features concerning verb, noun, article, word choice, tense, and preposition emerged predominantly. Furthermore, common phonological deviations included omission of final consonant sounds, mispronunciation of the schwa sound, confusion in pronouncing the article 'the,' mispronunciation of words ending with '-ine,' and substitution of /[open-mid back unrounded vowel]/ with /[open-mid back rounded vowel]/. The data suggests widespread use of non-standard English norms, indicating linguistic adaptation beyond traditional boundaries in various environments. Significantly, this study contributes by highlighting how ELF participants reshape language for effective communication, prioritizing intelligibility over nativelike proficiency, with insights extending beyond the Thai context, valuable for educators, linguists, and intercultural communication practitioners.