Area code 360

Area code 360 is a telephone area code in the North American Numbering Plan (NANP) for all of Washington state outside metropolitan Seattle and west of the Cascade Mountains. The numbering plan area (NPA) serves all of western Washington outside urban King, Pierce, and Snohomish counties and Bainbridge Island, Until January 15, 1995, when the area code commenced service, the numbering plan area (NPA) was served by area code 206, Washington's original area code since 1947.

Since 2017, area code 360 has been overlaid with area code 564. Additional NPAs in western Washington will be overlaid with 564 as well when numbering shortages demand relief.

From 1947 to 1957, all of Washington state was assigned area code 206 for routing long-distance telephone calls in Operator Toll Dialing. In 1957, the numbering plan area (NPA) was reduced to just the western part of the state, with most of the state east of the Cascade Mountains becoming area code 509.

Washington remained with two NPAs for 38 years. This configuration was unchanged even with western Washington's explosive growth in the second half of the 20th century and the proliferation of cell phones, fax machines, and pagers. By the early 1990s, the ensuing resource pressure meant that the need for additional central office prefixes and telephone numbers could no longer be staved off. Accordingly, of the region outside the Seattle and Tacoma areas was split from 206 to form a new numbering plan area with area code 360.

The 360 area code consists of two sections due to numbering disputes in the community. The configuration arose when residents of several Seattle exurbs protested their move from the more-established 206 to the new area code.^[1] In response, US West returned some central offices in these exurbs to 206. However, 206 was on the brink of exhaustion even after the creation of 360. The restoration of these exurbs forced the Washington Public Utilities Commission to switch most of Seattle's suburban ring into areas 253 and 425 in 1998, sooner than originally planned.

This made 360 one of the few NPAs in the North American Numbering Plan without a continuous land border;^[a] others include 706 in Georgia, 423 in Tennessee and 386 in Florida. Each case results from a split that removed the middle from a formerly contiguous area.

In 1999, the Washington Utilities and Transportation Commission intended to overlay 360 with an additional area code, but the implementation was delayed indefinitely. A 2016 report forecasted exhaustion in 2018.^[3] The change was finally approved in May 2016.^[4] On August 28, 2017 numbering plan area 360 was assigned the second area code, 564, to form an overlay numbering plan.^[5] Area code 564 is intended to eventually overlay other western Washington NPAs (206, 253, and 425) when demand requires numbering relief action.^[5] Beginning July 29, 2017 all calls in western Washington required ten-digit dialing.^[6] the first 564 prefix was assigned in 2021^{[7][8][disputed (for: Conflict between sources used)  – discuss]} and the final^[9] 360 prefix was assigned on October 22, 2021.^[8]

Area codes 360 and 334 (Alabama), which began service on the same day, were the first two area codes in the North American Numbering Plan with a middle digit other than 0 or 1.^[10]

The larger, western portion stretches from the Strait of Juan de Fuca through the Olympic Peninsula and Southwest Washington to the Oregon border, while the portion on the east shore of Puget Sound stretches from the border with British Columbia, Canada, almost to Everett. Whidbey Island in Puget Sound is also included.

Cities and towns in the numbering plan area include:

• List of Washington (state) area codes
• List of North American Numbering Plan area codes

• NANPA Washington area code map
• List of exchanges from AreaCodeDownload.com, 360 Area Code