The paper compares verbal responses of Czech and native English speakers to 12 model situations and analyses them in terms of Brown-Levinson’s politeness strategies (face-management theory). The survey aims to detect the pragmalinguistic features in Czech speakers’ English that can possibly lead to negative evaluation by English native speakers (i.e. can be seen as impolite). The results suggest that the Czech speakers failed to employ not only mitigation strategies in English, such as hedging, indirection and option-giving that seek to minimise the imposition conveyed by the FTA, but also intensification strategies that accentuate the illocutionary force of the FFA. The reasons that led to unintended impoliteness in non-native speakers included deficient pragmatic knowledge or generally poor English as well as different expectations about and evaluations of the given situations in English and Czech contexts. Such discrepancies are motivated by different cultural values and their hierarchies.