Ah yes, retainage, what could represent your profit on a project and something frequently abused by owners on private and public projects alike. Fortunately, Pennsylvania law offers public works contractors some protection from retainage abuse. The Public Prompt Payment Act dictates when retainage can be withheld and when it must be released. Agencies that fail to follow the Prompt Payment Act’s retainage rules can end up owing you interest, penalty, and attorney’s fees.