| 1947 |
4 area codes
214 – Northeast Texas
512 – Central and South Texas
713 – Southeast Texas
915 – West Texas |
| 1953 |
5 area codes
817 – a geographic split of the Fort Worth region from 214 |
| 1962 |
6 area codes
806 – a geographic split of the Amarillo/Lubbock region from 915 |
| 1983 |
7 area codes
409 – a geographic split from 713 |
| 1990 |
8 area codes
903 – a geographic split of the Longview region from 214 |
| 1992 |
9 area codes
210 – a geographic split of San Antonio from 512 |
| 1996 |
11 area codes
972 – a geographic split of the 214 area code serving the Dallas region
281 – a geographic split of the 713 area code serving the Houston region |
| 1997 |
15 area codes
254 and 940 – a three-way geographic split of 817
830 and 956 – a three-way split of 210 with San Antonio retaining that area code |
| 1998 |
15 area codes
The geographic boundary between 214 and 972 in Dallas is erased, creating the first overlay in Texas. Ten-digit dialing is required for local calls in that region. |
| 1999 |
18 area codes
The geographic boundary between 713 and 281 in Houston is erased, creating an overlay and requiring ten-digit dialing for local calls in that region.
832 – an overlay added as the third Houston area code
361 – a geographic split of 512 creates a new area code for the Corpus Christi region
469 – an overlay added as the third Dallas area code |
| 2000 |
21 area codes
979 and 936 - a three-way split of 409 with Beaumont retaining that area code
682 – an overlay added to 817 for Fort Worth and part of Northeast Texas |
| 2001 |
21 area codes
Due to number reclamation, number pooling, and other number conservation measures, no new area codes become operational. |
| 2002 |
21 area codes
Due to number reclamation, number pooling, and other number conservation measures, no new area codes become operational
|
| 2003 |
24 area codes
430 - an overlay is announced for 903. It became operational in April, 2003
432 and 325 – a three-way split of 915 with El Paso retaining that area code. The new codes became operational in April, 2003 |