Calling Card
A telecommunication credit card with an AuthCode (authorization code) for using a long distance carrier when the customer is away from their home or office (ANI).

Carrier
A telecommunications provider which owns switch equipment.

Carrier Line Charge - See PICC.

CHCF-A, CHCF-B - See USF.

Country Code
Two or three digit codes used for International calls outside of the North American Numbering Plan area codes. Dial: 011 + country code + city code + local phone number) (e.g. "011 + 91 + 22 + 123- 4567" 91 = India, 22 = Bombay).

Cramming
The practice of placing unauthorized, misleading, or deceptive charges on your telephone bill. Entities that fraudulently cram people appear to rely largely on confusing telephone bills in order to mislead consumers into paying for services that they did not authorize or receive. What the FCC has to say about it

Customer Line Charge - See Federal Subscriber Line Charge.

Cutover
The exact date/time that a phone number, circuit, etc. is scheduled to be (or was) moved from one implementation (carrier, etc.) to another. (e.g. moving an 800 number from MCI to Planet Earth).