Area code 859
Its service area encompasses 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 in the 859 territory 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 numbers 859 spell out "UKY" on a standard keypad—a nod to Lexington being home of the University of Kentucky.
When an area code is split, normal practice calls for the largest city to retain the old area code in order to minimize disruption. Thus, conventional wisdom would have suggested that Lexington and Northern Kentucky would 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 in order 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 for the foreseeable future, and is nowhere near exhaustion. 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.
Area code 859 has telephone numbers assigned for the central office code 988. 988 has been designated nationwide as a dialing code for the National Suicide Prevention Lifeline, which creates a conflict for exchanges that permit seven-digit dialing. This area code is therefore scheduled to transition to ten-digit dialing, mandatory after October 24, 2021.
- "Transition to 10-digit dialing (for 988 as 3-digit access to National Suicide Prevention Hotline)" (PDF). NANPA. January 8, 2021. Retrieved March 9, 2021.
|West: 502, 812/930||area code 859||East: 606|
|Indiana area codes: 219, 260, 317/463, 574, 765, 812/930|
|Ohio area codes: 216, 220/740, 234/330, 380/614, 419/567, 440, 513, 937/326|