A sinking fund is a fund containing money set aside or saved to pay off a debt or bond. A company that issues debt will need to pay that debt off in the future.) Have the custody, investment and management of any sinking funds provided for the payment or redemption of County debts. A sinking fund is a savings method that will help you accomplish your financial goals. Explore what a sinking fund is and how to use one. Funds can be transferred for use with. Legislature approval. A sinking fund call is a provision that allows a bond issuer to buy back its outstanding bonds before their maturity date at a pre-set price. Next Sinking Fund Installment to become due on the Bonds. Second, an amount equal to replenish any deficiencies in the Debt Service Reserve Fund, if any;.