California area codes 619 and 858 currently cover the southern and northern parts of San Diego respectively, including some of its suburbs. On April 17, 2017 the California Public Utilities Commission approved a boundary removal between the two Numbering Plan Areas. The decision will take the pressure off area code 619, which is approaching exhaustion. The resulting overlay complex 619/858 will cover the entire area currently served by the two area codes and will have as a side effect mandatory 1+10 digit dialing for all telephone calls within the area.
- November 11, 2017 – permissive 1+10 digit dialing begins (1+10 digit dialing is encouraged for all calls)
- May 19, 2018 – mandatory 1+10 digit dialing begins
- June 19, 2018 – the new overlay complex 619/858 enters service
See official announcement and other helpful info (PDF document)