Q. When did CMOS discontinue the use of “p.” and “pp.” before page numbers in notes? Furthermore, is it currently acceptable to employ these abbreviations if they align with the preferred house style at an institution?
A. The Chicago Manual of Style has never required “p.” or “pp.” in source citations. The first edition of the Manual (1906), in a three-page section on footnotes, included the following advice: “Ordinarily, omit ‘Vol.,’ ‘chap.,’ and ‘p.’ in references to particular passages” (¶ 218).
This advice is intended to cut down on clutter and repetition, but it isn’t an outright ban, as the current edition of CMOS (in paragraph 14.151) clarifies:
Where the presence of other numerals threatens ambiguity, p. or pp. may be added for clarity. (And if an author has used p. and pp. consistently throughout a work, there is no need to delete them.)
In other words, there’s nothing wrong with “p.” and “pp.” Besides, when a house style contradicts CMOS, the former generally takes precedence.