Number holder
Frontier California
NANPA assigned Frontier California 1,074 of the 197,646 central office codes in service, <1% of the total. Rank 33 of 36 listed holders.
What kind of holder this is
Landline telephone company. Frontier describes its service on its home page as fiber internet, TV and phone for homes and businesses; the holder is a Frontier operating company. Source page, read 2026-10-19.
Prefixes held
Prefixes held
1,074
of 197,646 in service (<1%)
States and territories
1
Area codes
21
Pooled prefixes
396
37% of its prefixes
Registered as Frontier California INC., under 3 operating company numbers.
Prefixes by state or territory
| State or territory | Prefixes |
|---|---|
| CA | 1,074 |
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.