New York City telephone exchanges

The history of the telephone exchange names in New York City can be divided into three periods:

1. The pre-dial period, covering directories dated prior to November 17, 1920 (the last being dated May 1920), when all telephone calls were completed by manual action by operators, and there were no constraints on exchange names other than that there was no likelihood of confusion when a customer gave the name to the operator,
2. The early dial period, beginning with the November 17, 1920 dated directory, in which the directory format was set up to accommodate dialing the first three letters of an exchange name followed by a four-digit (usually; some few numbers had five) number designating the individual line, though in fact not all exchanges provided for dialing by the phones in those exchanges. (In fact, one exchange in City Island, the Bronx, retained manual operation until 1960!), and
3. The late dial period, beginning with the directory dated Winter 1930, in which, instead of the first three letters of an exchange name, one dialed only the first two letters and an "office number" (This was the terminology used in the Winter 1930 directory, though it was not common terminology in this period), again followed by (usually) four digits designating the individual line. Although, in 1930, New York City was alone in using this pattern, it eventually became the common format for dialed telephone numbers in the United states until the advent of All-Number-Calling in the 1960s.

It should be noted that on this site we do not refer to the pre-dial period as the "manual" period, because (as noted above) manual exchanges continued to exist for many years into the dial period. What distinguishes the pre-dial period from the early (and late) dial period was not the presence of manual exchanges, but the absence of dial exchanges.

The varied changes in directory formats during these three periods are separately discussed in the pages covering each individual period (which can be reached by clicking the appropriate links either in the preceding paragraph or in the table listing the chronological periods below).

This site includes information about other telephone numbers northward and eastward of New York City, because some of those numbers became dialable from the city after about 1950, while others were, in turn, connected with those suburban numbers by being assigned the same area codes when area codes were instituted, and as a result they affected the availability of exchange names. (See this page for more information.)

Last modified January 15, 2011.