This article focuses on socio-pragmatic aspects of address forms in seventeenth- and eighteenth-century personal letters in the Corpus of Early English Correspondence (CEEC) by comparing the forms found inside and on the outside of a letter. In addition to providing a wider social perspective, the research questions concern the private and public aspects of address formulae and the influence of different participant roles of the writer and the recipient. Address forms are analysed using Bell’s (1984, 2001) audience design model, as well as Brown and Levinson’s (1987) theory of politeness.