R.G. Dun & Company, now known as Dun & Bradstreet, was a credit reporting agency that provided ratings on an enterprise’s financial strength and ability to pay back debts. This was useful information for those interested in doing business with or lending money to a particular company. Dun & Company published quarterly credit ratings on the merchants, manufacturers, and traders in the United States and Canada. This publication was originally published by the Mercantile Agency, part of R.G. Dun & Company, and titled Reference Book. R.G. Dun merged with Bradstreet in 1933, which continued producing these volumes, later known as Reference Book of American Business, until 2006.

The Library’s collection is nearly complete, starting in 1859; publication was suspended from 1861 to 1863 during the beginning of the American Civil War. The volumes were published multiple times a year although the frequency did change over time. This particular collection contains volumes of the Reference Book from 1859 to 1924.

The organization of the title and the information included have changed throughout its publication history, but generally speaking, the business entries are organized alphabetically by state or territory, and then city/county, with sections on Canada, alphabetically by province, located at the end of the volumes. Originally, New York was listed first, as this was the headquarters of the Mercantile Agency, although in at least one case, in 1871, Philadelphia was listed first. A detailed map of each state is included at the beginning of each state section, except for the District of Columbia and Delaware, which can be found on the map of Maryland. In addition to detailed geographic maps, there are also abstract maps of distances between major cities, sometimes with railroad fares. Territories that would later become states are usually included alphabetically in volumes dated well before their statehood. Of special note are the Hawaiian Islands, which were included in the 1871 edition alongside the Canadian listings.

An individual company listing includes the business name, the company’s business type, financial strength, and credit rating but does not include business owner names or addresses. Prior to the introduction of the Standard Industry Classification codes, a symbol was used to indicate the industry. These credit ratings do not cover every industry and focus primarily on manufacturing and retail so establishments for lawyers, dentists, educators, doctors, and hairdressers are not included. The key to industries and ratings changed slightly over time but is usually found in the front cover of the book though sometimes it is placed at the end. The letter and number correspond to the rating of financial strength and credit appraisal. We have compiled a list of direct links to keys in the digitized volumes as part of the Guide to Dun & Bradstreet Publications at the Library of Congress.

The Reference Book also includes information on banks and for a time, fire insurance companies. Some years also have a “Status of Fire Insurance Companies List” and “Negotiable Instruments Law,” the latter a precursor to the Uniform Commercial Code. Early volumes grouped bank and fire insurance companies’ information at the back of the volume, while later volumes placed bank and legal information at the end of each state’s entry.

The historical Dun & Bradstreet handwritten credit reports, which are held by Harvard University, are a separate collection from these published volumes.