Area code 641

Area code 641 is a telephone area code for a central portion of Iowa, including Mason City, and Ottumwa. It was split off from area 515 on July 9, 2000; this was the first such split in Iowa since the establishment of the North American Numbering Plan in 1947.

The map to the right is clickable: click on any of the area codes on the map to go to the area code for that region.

A large number of calling card and conference service providers operate in area 641. When one calls a rural number in area 641, the long distance provider has to pay the termination fee to the receiving telecom party: up to 8 cents a minute. Using this arbitrage, some of the service providers operate here and require one to dial the 'local access number' in area 641. Large telecom providers are the hardest hit with the costs for these so-called free service providers. AT&T filed a suit to withhold these arbitrage payments (AT&T got a $2 million bill a month). (March 2007)

In 2006, various companies began using Iowa's 641 as a number to access voice over IP gateways, including one which purported to allow users to "call China for free". The scheme, no longer in operation, was based on the wholesale cost of calls to rural Iowa being substantially more than the cost of Internet calls to China.

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