Longest Path vs Critical Path

Many assume they are the same but they’re not.

Critical Path: Activities with zero or less (or defined) total float. Multiple critical paths can exist, each showing potential delays.

Longest Path: The single path that drives the project completion date. It reflects the overall project delay and forecasted finish.

In Primavera, filters distinguish both: “Critical” by float definition, and “Longest Path” by completion driver. Understanding this difference is essential for accurate schedule analysis and delay assessment.