4-1-1

4-1-1 is the telephone number for local directory assistance in the United States and Canada.

4-1-1 is also commonly referred to as "D.A.", "Directory Assistance", or "Information".

Approximately 6 billion calls are made to 4-1-1 within the United States every year.

4-1-1 has been used since at least 1930 in New York City,San Francisco, and other large cities where panel and crossbar switching equipment installed by the Bell System was prevalent. However, in smaller Bell System cities and almost all areas served by GTE and other companies where step-by-step equipment was the norm such as Los Angeles,1-1-3 was used until at least the 1960s, and in some cases (the Pacific Northwest, for example) until the mid-1980s.

Until the early 1980s, 4-1-1 and 1-1-3 calls were free in most states.

In the United States and Canada, Directory Assistance was historically a local function, and most companies updated listings at their directory assistance centers almost daily. Callers would dial 4-1-1 or 1-1-3 for fast, efficient, and accurate service. When long-distance numbers were needed, prior to the full introduction of direct-dialed long-distance service, callers would call either 4-1-1 or "0" (Operator) and request a free long-distance connection to the directory assistance center in the distant city.

In 1962, direct-dialed long-distance directory assistance became available. The number in cities with panel and crossbar switching equipment was area code-555-1212, whereas in cities with step-by-step equipment the number was 1-555-1212 (or 112-555-1212) for numbers not local but in the same area code and 1-area code-555-1212 (or 112-area code-555-1212) for numbers in other area codes. In some area codes, the directory assistance center was able to serve the entire area code, but in many, the operator in the principal city of the area code dialed would connect the caller onward to a more local directory assistance center for the most up-to-date information.

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