Number holder
Southwestern Bell
NANPA assigned Southwestern Bell 5,971 of the 197,646 central office codes in service, 3% of the total. Rank 6 of 36 listed holders.
What kind of holder this is
Landline telephone company. AT&T's consumer service terms name Southwestern Bell Telephone Company among the AT&T companies that provide AT&T Phone Service, a wireline home phone service. Source page, read 2026-10-19.
Prefixes held
Prefixes held
5,971
of 197,646 in service (3%)
States and territories
6
Area codes
43
Pooled prefixes
3,516
59% of its prefixes
Registered as Southwestern Bell, under 1 operating company number.
Prefixes by state or territory
| State or territory | Prefixes |
|---|---|
| TX | 3,527 |
| MO | 849 |
| OK | 624 |
| KS | 567 |
| AR | 402 |
| IL | 2 |
Prefixes by area code
Read this before you rely on it
The holder is the company NANPA assigned the codes to, under the legal name it registered. That name can differ from the brand customers see, and one brand can hold codes under several legal names.
Numbers port. A number in one of these prefixes may now be with another carrier, so the prefix alone does not say who serves it today. To see the holder of the block behind a number, use the carrier lookup.
Source: NANPA central office code report dated 2026-10-17 and thousands-block report dated 2026-10-17.