Area code 414

North American telephone area code 414 is a state of Wisconsin area code which was created along with area code 715 as one of the two original area codes assigned to Wisconsin in October 1947. Currently, the 414 area code is nearly exclusive to Milwaukee County, including the city of Milwaukee. However, a few small portions of Muskego and Brookfield, in Waukesha County, along with the small industrial "Ambrosia triangle" which is a part of Milwaukee in southeast Washington County are also part of this area code.

The 414 area code originally covered most of the southern and northeastern portions of Wisconsin, with 715 covering the northwest. It was first split in 1955, when much of the western portion (including Madison) was split off as 608. This configuration remained in place until July 26, 1997, when the northern half (including Green Bay and the Fox River Valley) became the 920 area code.

The creation of 920 was intended as a long-term solution, but within a year 414 was close to exhaustion once again due to the proliferation of cell phones and pagers. In 1998, NANPA assigned area code 262 as a second area code for southeastern Wisconsin. The initial proposal called for 262 to be an overlay for the 414 territory. However, overlays were a new concept at the time, and met with considerable resistance due to the requirement for ten-digit dialing. Additionally, several Milwaukee businesses objected to the possible expense of changing their numbers. As a result, it was decided to implement 262 as a geographic split, with nearly all of the old 414 territory outside of Milwaukee County getting the new area code. The split took effect on September 25, 1999.

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