Significant events for area code 408
| Date |
Details |
| January 1, 1959 | Area code 415 was split three ways, with 707 covering the north coastal area and 408 covering the South Bay Area |
| July 11, 1998 | Area code 408 was split with 831 covering Santa Cruz, Monterey and San Benito Counties. |
| November 20, 2012 | Area code 669 was overlaid on 408. |