Area code 859

Area code 859 is a telephone area code in the North American Numbering Plan (NANP) for the city of Lexington and the central portion of the Commonwealth of Kentucky. It was created in a split from area code 606 in 1999.

History
Area code 859 was created in a split from area code 606 in 1999.

When an area code is split, normal practice calls for the largest city to retain the old area code in order to minimize disruption to existing businesses and the community. Thus, conventional wisdom would have suggested that Lexington and Northern Kentucky should have retained 606 in the 1999 split. Lexington was by far the largest city in the old 606 territory. Combined, Lexington and Northern Kentucky accounted for two-thirds of the old 606's population, along with the great majority of its landlines and cell phones. However, several counties in eastern Kentucky are among the poorest in the nation. The Kentucky Public Service Commission and BellSouth (now part of AT&T), then the region's main telephone carrier, decided to let the rural portion retain 606 to spare this notoriously impoverished area the added expense and burden of switching to a new area code.

Under current projections, 859 is expected to remain in its current configuration until about 2047. This is despite the fact that the Cincinnati local toll area extends into both Northern Kentucky and southern Indiana, meaning that several numbers in Cincinnati's 513 and the Indiana suburbs' 812/930 are not available for use.

Prior to October 2021, area code 859 had telephone numbers assigned for the central office code 988. In 2020, 988 was designated nationwide as a dialing code for the National Suicide Prevention Lifeline, which created a conflict for exchanges that permit seven-digit dialing. This area code was therefore scheduled to transition to ten-digit dialing by October 24, 2021.

Service area
The numbering plan area comprises the following Kentucky counties. The boundary closely, but not exactly, tracks county lines.
 * Boone County
 * Bourbon County
 * Boyle County
 * Campbell County
 * Clark County
 * Fayette County (coterminous with the city of Lexington)
 * Gallatin County
 * Garrard County
 * Grant County
 * Harrison County
 * Jessamine County
 * Kenton County
 * Madison County
 * Mercer County
 * Montgomery County
 * Nicholas County
 * Pendleton County
 * Washington County
 * Woodford County

By far the largest city is Lexington. The next largest area is Northern Kentucky, the Kentucky portion of the Cincinnati metropolitan area. It includes smaller cities and towns such as Nicholasville, Richmond, Danville, Covington, Versailles, Florence, Mount Sterling and Winchester.

The digits 859 spell out "UKY" on a standard telephone keypad—a nod to Lexington being home of the University of Kentucky.