Give it a +1 - the North American Number Plan Association (NANPA)

If you've ever called a telephone number in a country other than your own, then you've probably have some experience with country codes. For example, if you live in France but want to call someone in Serbia, you need to use the country code 381 to do so.

But things are a little different in North America. If a French person wants to dial the United States, he or she would use the country code 1. How about Canada? The country code 1. Bermuda? The country code 1.

Basically, in 1964 the world was divided into several zones for calling purposes. Most of these were regional zones - for example, World Zone 2 (Africa) included separate country codes for the countries and territories within Africa. There were two major exceptions - the USSR, which in 1964 had the country code +7, and North America, which had a country code of +1.

North America calling had been organized long before the CCITT (now the ITU) had divided the world up. In fact, initial organization was not undertaken by a governmental agency, but by a private company - American Telephone & Telegraph (AT&T) - in 1947. As of 1964, the North American Numbering Plan covered the following countries and territories:

Bahamas, Bermuda, British Honduras [now Belize], Canada, Costa Rica, El Salvador, French Antilles, Guatemala, Honduras, Jamaica, Mexico, Netherlands Antilles, Nicaragua, Panama, Puerto Rico, USA, US Virgin Islands.

Today, the list is slightly different. Beginning in 1968, some of the countries above were moved to World Zone 5, and other countries/territories were added. Today, the list looks like this:

...the United States and its territories, Canada, Bermuda, Anguilla, Antigua & Barbuda, the Bahamas, Barbados, the British Virgin Islands, the Cayman Islands, Dominica, the Dominican Republic, Grenada, Jamaica, Montserrat, Sint Maarten, St. Kitts and Nevis, St. Lucia, St. Vincent and the Grenadines, Trinidad and Tobago, and Turks & Caicos.

The North American Numbering Plan is administered by an entity known as the North American Numbering Plan Administration. Unlike other entities, the NANPA itself can change over time:

Since 1997, the FCC has selected the company that serves as NANPA through a competitive bidding process. In 1997, Neustar (then Lockheed Martin IMS) was selected to serve for a five-year term as NANPA. In 2003, Neustar was again selected to serve an additional five year term beginning in July, 2003. In 2009, Neustar was awarded an 18 month contract to continue to provide NANPA services through January 2011.

However, there are also national administrators for many of the countries within the NANP. Neustar is the administrator for the U.S., while SAIC Canada is the administrator for Canada.

For most of the countries in the NANP, it's pretty easy to track the area codes assigned to the country. In many cases, there's only one area code. Consult http://www.nanpa.com/pdf/NANP_Member_Country_Maps.pdf for a list of the area codes for most countries.

It's a little more complicated in Canada and the United States, where populations are so large that single cities such as Toronto and Los Angeles may have multiple area codes within the same city. This is clearly a change from the original US/Canada area code assignments in 1947. Some of the changes between 1947 and the present day:

The 916 area code in northern California included Eureka and the north coast, but not Sacramento. It is the only one of the original codes that now includes none of its original territory.

Florida had only one area code in 1947; as of 2010, it has seventeen.

The 914 area code included not only the suburbs north of New York City, but also Long Island.

The three area codes in Iowa and four in Ohio lasted until the mid-1990's.

In 1947, 34 states plus D.C. had only a single area code each. In 2010, only 10 of those 34, plus D.C., Alaska, and Hawaii, have single codes.

Also note that some areas, such as Alaska and Hawaii, didn't have area codes in 1947. But that wasn't much of an issue, since telephone users couldn't direct-dial area codes anyway; the area codes were for the benefit of the operators. But that would change in a few short years:

Nov. 10, 1951: Mayor M. Leslie Downing of Englewood, N.J., picked up a telephone and dialed 10 digits. Eighteen seconds later, he reached Mayor Frank Osborne in Alameda, Calif. The mayors made history as they chatted in the first customer-dialed long-distance call, one that introduced area codes....

The mayors' call proved a vast improvement over the first transcontinental telephone call 36 years earlier, when it took five operators 23 minutes to set up a call from San Francisco to New York. For many years, long-distance calls required an operator at the calling end and another at the receiving end. More operators were often needed at intermediate points to build the route through the network one segment at a time.

With a whopping ninety area codes in 1951, and room for expansion, everything seemed fine - until we ran out of area codes in 1995. We jiggled the numbering system, allowing hundreds of area codes, and that should be enough for us...for a little while.