Texas law seems pretty clear about it...

33A.04. Theft of Telecommunications Service

(a) A person commits an offense if the person knowingly obtains or attempts to obtain telecommunications service to avoid or cause another person to avoid a lawful charge for that service by using:

(1) a telecommunications access device without the authority or consent of the subscriber or lawful holder of the device or pursuant to an agreement for an exchange of value with the subscriber or lawful holder of the device to allow another person to use the device;