Greetings and farewells mark the boundaries of conversations; they are often formulaic and are generally claimed to be devoid of propositional content. However, they are often embedded in longer exchanges, and within such exchanges individual expressions may or may not have propositional content. This contribution discusses some of the inherent problems of retrieving speech acts, such as greetings and farewells, from a corpus. This is illustrated with a diachronic analysis of greetings and farewells in two hundred years of American English as documented in the 400-million-word Corpus of Historical American English (COHA). In the nineteenth century, the most frequent greetings were “good morning” and “how are you?” and the most frequent leave-taking expression was farewell while in Present-day American English the expressions hi and hello dominate as greetings and goodbye and “bye bye” as leave-taking expressions. The two phrases “how do you do?” and “how are you?” serve as examples that show how formulaic and literal uses have coexisted over the entire period covered by COHA, with a shift from a predominance of literal uses to a predominance of formulaic uses, particularly in the case of “how do you do?”. However, both phrases remain ambiguous in their uses. The interactants discursively assign a more literal or more formulaic force to them.