New Washington area code 564

The more populous, western part of Washington State is currently served by 4 area codes: 206, 253, 360 and 425. The Washington Utilities and Transportation Commission approved on May 19, 2016 the introduction of the new area code 564 which will initially overlay area code 360 and eventually the entire area currently served by the 4 aforementioned NPAs.

Key dates

  • January 17, 2017 – start of permissive 7/10 digit dialing period for all 4 NPAs (206, 253, 360 and 425); during the permissive period local calls may be dialed using either 7 or 10 digits
  • July 29, 2017 – start of mandatory 10 digit dialing (it is not clear whether the mandatory 10 digit dialing applies to all 4 NPA or just NPA 360 – the official planning letter below also suggests that mandatory 10 digit dialing will be implemented for all 4 NPAs by September 30, 2017)
  • August 28, 2017 – new area code 564 enters service, overlaying area code 360

Plans for NPAs’ 206, 253 and 425 relief will be announced at a later time.

See official NANPA announcement and map of the new overlay area (PDF document)

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