A predictive dialer is a computerized system that automatically dials batches of telephone numbers that connect to agents assigned to sales or other campaigns. Predictive dialers are widely used in call centers.

Predictive dialers were developed from the auto dialer. While the basic auto dialer merely automatically dials telephone numbers for call center agents who are idle or waiting for a call, the predictive dialer uses a variety of algorithms to predict both the availability of agents and called party answers, adjusting the calling process to the number of agents it anticipates or predicts will be available when the calls are answered.

The predictive dialer monitors the answers to the calls it places, detecting how the calls it makes are answered. It discards unanswered calls, engaged numbers, disconnected lines, answers from fax machines, answering machines and similar automated services. It only connects calls answered by people to waiting sales representatives. Thus, it frees agents from listening to unanswered or unsuccessful calls.

A predictive dialer can dramatically increase the time an agent spends on communication rather than on waiting. The system is most suitable for low quality lists and large numbers of agents, as a high contact rate can overwhelm the system.

Predictive dialer systems are commonly used by telemarketing organizations involved in business to consumer calling as it allows their sales representatives to have much more customer contact time.

More commonly predictive dialers are being used as a quick and easy way to automate all sorts of calls that would otherwise be made manually by a call center. These include welcome calls for new customers, customer service callbacks, appointment confirmations, or the automation of large numbers of ad hoc calls that might take place (by a taxi company, or parcel delivery service etc.).