Current retainage is not always the cumulative retainage total
A progress billing application usually shows completed work cumulatively. If the software subtracts the full cumulative retainage from only the current period’s work, the contractor can be underbilled. BuildDue records prior completed work and prior retainage separately so the current request reflects the period’s actual retainage change.
Retainage terms vary by contract, project type, and jurisdiction. The calculator is a planning tool, not legal or accounting advice.