Politeness plays an important role in academic interaction, particularly when students communicate across different interpersonal relationships and cultural contexts. This study investigates politeness strategies employed by Indonesian and Malaysian university students, compares their realizations across academic speech-act situations, and identifies emerging cross-cultural patterns. A qualitative descriptive design within a cross-cultural pragmatic framework was employed. Data were collected through a Discourse Completion Task comprising 20 parallel academic situations involving requests, refusals, disagreement, criticism and evaluation, apologies, gratitude, and digital academic communication. The participants were 20 Indonesian and 18 Malaysian students, generating 760 valid responses for analysis. The responses were coded for directness, mitigation, apology, explanation, deference, appreciation, hedging, alternative offering, and relational orientation. The findings reveal that both groups employed broadly similar pragmatic resources but differed in their degree of elaboration and strategy combination. Indonesian students tended to construct more elaborated responses through mitigation, hedging, appreciation, deference, and relational orientation, whereas Malaysian students demonstrated greater variation between concise and elaborated realizations and more frequent direct formulations. Stronger convergence occurred in apologies and expressions of gratitude. Interlocutor relationships also influenced strategy selection, with lecturer-directed communication showing greater sensitivity to hierarchy than peer interaction. These findings highlight the importance of pragmatic elaboration and relational context in understanding academic politeness across closely related Southeast Asian settings.