This study explores how Chinese university EFL learners accept and utilise ChatGPT, employing the widely recognised UTAUT2 model. A quantitative approach was utilised, collecting data from 340 participants through an online questionnaire and analysing it using structural equation modelling (SEM). The results indicate that habitual behaviour considerably influences students' behavioural intentions (BI) and actual use behaviour (UB), underscoring the importance of fostering regular engagement with ChatGPT. Performance expectancy and social influence also positively impact BI, whereas hedonic motivation, effort expectancy, and price value show non-significant effects. Interestingly, facilitating conditions exert a significant influence on actual use behaviour, despite their weak influence on BI. The study contrasts with prior research by highlighting the minimal impact of behavioural intention on actual use, suggesting that habit and supporting resources are more critical in this context. These findings offer invaluable insights for educators and policymakers aiming to incorporate AI tools into language learning curricula, emphasising the need for habitual use and clear communication of ChatGPT's benefits.