A forecast is a projection of a project’s future state – such as its likely final cost or completion date – based on the information available now, including performance to date. Forecasts turn current data into an estimate of where the project is heading.
In earned value, forecasts such as the estimate at completion are calculated from performance indexes. More broadly, teams also forecast using flow metrics and probabilistic methods. A forecast is an estimate, not a promise, and is updated as new data arrives.
Related: estimate at completion, throughput, estimate.
Last updated: 4 July 2026 · By Tom, PMP-certified since 2004