Principal Repayment Schedule Posted on 14th December 201512th October 2020 by ThePD (The Project Definition) A Principal Repayment Schedule is a repayment schedule of principal by instalment amount and due date. Click to share on Twitter (Opens in new window)Click to share on Facebook (Opens in new window)Click to share on LinkedIn (Opens in new window) Related Posted in Business and tagged commercial. ThePD (The Project Definition) ThePD has been developing the Preferred Project Definitions based on the actual project execution and operation experiences and knowledge with the Project Language, and sharing with you daily basis.