Intelligent telephone call routing

A method comprising:

• maintaining, by a call monitor of a telephone system, a session log in which a plurality of call session records relating to telephone calls between internal extension numbers and external telephone numbers are stored, wherein each of the internal extension numbers are associated with a telephone extension within the telephone system and each of the external telephone numbers are associated with a telephone outside of the telephone system;
• receiving, by the call monitor, an incoming telephone call from a telephone outside of the telephone system, wherein the telephone outside of the telephone system is associated with an external telephone number;
• searching, by the call monitor, the session log for a call session record of the plurality of call session records corresponding to the external telephone number of the incoming telephone call;
• calculating, by the call monitor, a probability score that the incoming telephone call is a call-back of an internal extension number within one or more matching call session records;
• playing, by the telephone system, a prompt message to the external telephone number wherein the prompt message indicates that the incoming telephone call will be routed to the internal extension number within one or more matching call session records;
• and
• when (i) a result of the searching meets one or more predetermined or configurable conditions and (ii) the probability score is higher than a predetermined threshold, then causing, by the call monitor, a switch of the telephone system to route the incoming telephone call to the internal extension number of the internal extension numbers.