Nevertheless, phone sex should not be confused with prostitution wherein money is exchanged for real life sexual services or physical interactions.
When the Internet got relatively mature, sale of any sexual service not involving a minor could be made to anyone not a minor.
Software platforms were custom written to handle money collection and transfer, connecting caller and sex worker though neither could see anything but the platform's phone number, and metering the connection.
(This attitude still survives among some providers.) When public (mostly female) pressure forced the phone companies to stop providing this service to sex workers, a transition was made to a manual method: pre-paid blocks of time, 10, 30, 60 minutes, whatever the customer would pay for.
The incentives for providers were then reversed; rather than earning money from keeping the customer on the line (orgasm delayed), they earned more from bringing the caller to orgasm quickly, so as to move on rapidly to another call.
By 2007 only Verizon, Sprint and AT&T remained in the chat line business in the U. By 2007 Verizon and MCI had merged and only a few chat line companies remained active as a result.