Significant events for area code 201
| Date |
Details |
| 1947 | Original area code for New Jersey. |
| 1958 | Area code 201 was split, with 609 covering the southern part of the state. |
| June 8, 1991 | Area code 201 was split, with 908 covering the southern part of the area. |
| June 1, 1997 | Area code 201 was split, with 973 covering the central area. |
| December 1, 2001 | Area code 551 was ovelaid on 201. |