The Internet Archive hosts copies of some, but not all, years of the Boston Directory. This page attempts to pull together in one place links to these freely available digitized directories. If you know of additional years for the Boston Directory let us know at research@bpl.org.
Most years of the Boston city directories can be accessed via our subscription to Ancestry Library Edition while in the library. This is the easiest and most convenient way to use them. You can use a search box or view complete scanned pages and search visually. The second method is recommended if you are searching a common name or to double check if the search engine is not finding the results you expected or wanted. The search engine is helpful but not 100% reliable in deciphering the old printed volumes. Please ask a librarian if you need help getting started using them this way.
The Boston Public Library also holds microfilm copies of the Boston city directories for 1789-1960. For the year 1961-1981 paper copies are available if the digital version is missing or otherwise not usable for some reason. These can be requested at the Research Services Desk on the 2nd floor of the Central Library in Copley Square with a library card.