Significant events for area code 604
| Date |
Details |
| 1947 | The original area code for British Columbia |
| October 19, 1996 | Area code 604 was split with 250 covering all but the southern area of British Columbia |
| November 3, 2001 | Area code 778 was overlaid only on the southwestern (Vancouver) area |
| July 4, 2007 | Area code 778 was expanded to cover the entire province. |
| Several area codes have been "overlaid" onto the entire province. |