A pragmatic routine formula is any expression with a stable form that is commonly repeated in the routinized social interactions of a given culture. Previous research has reported that such pragmatic routine formulae are often underused by foreign language learners, even when they have been studying the language for a long time. To explore the reasons for this underuse, this study investigated the development of 59 Chinese as a foreign language (CFL) learners’ recognition and production of pragmatic routine formulae in situations they might encounter in China. Results showed that length of stay in the target language country had a significant effect on recognition but not on production. CFL learners with longer periods of residence abroad were able to recognize more pragmatic routine formulae, but which specific formulae were recognized depended on the interactional settings in which learners had engaged. Further analysis revealed that learning challenges may arise in three kinds of situations: (1) those requiring a pragmatic formula in the target language but a different formula in the learner’s native language, (2) those requiring a routine formula in the target language but no remarks in the native language, and (3) those in which the learner overgeneralizes a more familiar form.