Request performances can be influenced by contextual factors. This paper examines the explanations of the request formulations of six Vietnamese learners of English in Australia. The retrospective interviews provide interesting insights into learners’ request wording, such as the underlying motivations and reasoning, that are not apparent in traditional analyses of the forms. First, an analysis of learners’ contextual perceptions shows that age differences, perceptions of the relative role relationship, and the formality of the situation influence their request formulation. Second, learners’ judgements of politeness and their reported use of politeness devices suggest that learners may rely on supportive moves to manage harmony with their interlocutors. Therefore, the study suggests that appeal to alternative sociopragmatic interpretations could be the main reason for the differences in making requests between Vietnamese learners of English and English native speakers. The findings may advocate the explicit teaching of request speech acts for Vietnamese learners.