Predictive vs Progressive vs Preview Dialing: When to Use Each

The dialing mode you choose for a campaign is the single most impactful configuration decision in outbound calling. It determines how many contacts your agents make per hour, how much idle time they endure between calls, how many leads you burn through per shift, and whether your operation stays on the right side of FCC and TCPA regulations. Get it wrong and you either leave money on the table (too conservative) or catch a compliance violation that costs more than a month of revenue (too aggressive). Despite this, most call center operators either stick with whatever their dialer defaulted to, or switch to "predictive" because someone told them it was faster — without understanding the trade-offs, the agent count thresholds, or the compliance implications. This guide covers the three primary dialing modes in depth: predictive, progressive, and preview. For each mode, we explain how it works technically, how VICIdial implements it, when to use it, and what performance to expect. We also