Internationalisation of higher education greatly facilitates cross-border student mobility, which has been extensively researched. This comparative study focuses on the relatively under-explored field of intra-regional educational mobility. It compares attitudes towards learning and using English of Mainland Chinese students and Hong Kong Chinese students while studying side-by-side at an English-medium university in Hong Kong. Using a mixed methodology the study found that the two groups expressed a similarly strong need for, and acceptance of, English as an academic "lingua franca" but expressed significantly different attitudes, needs and desires in relation to the use of English for social intercourse. The weaker presence of a social "lingua franca" was accompanied by perceptions of a lack of inclusivity. If, as is suggested in the literature, both social and academic integration are integral to the university experience, the findings reveal a lacuna in the learning environment of this and potentially other similarly internationalised universities.