The aim of this study was to investigate the use of the native Finnish politeness marker kiitos 'thank you/please' compared to the borrowed politeness marker pliis (from English please). Pliis in Finnish is best characterized as a marked form which is mostly relegated to informal or spoken language. Thus, this stage of our study made use of a grammatical acceptability test to try to observe social evaluation patterns. The test was presented as a web-based survey consisting of 12 grammatical acceptability questions and 6 demographic questions. It was completed by 417 respondents from throughout Finland. The hypothesis was that the function of kiitos could be changing grammatically and semantically. However, the findings indicate that the use of kiitos is more or less unchanged, whereas the use of pliis is likely to be nativizing. The MANOVA analyses indicate that pliis is associated (as a first order index) with young, urban women, and this is also the social group that is more likely to claim use of pliis. The most important finding of the study is that pliis and kiitos seem to be complementary in their distribution; grammatically, pragmatically and in terms of social distinctiveness. We claim that kiitos serves as a marker of negative politeness, whereas pliis serves as a marker of positive politeness.