The broad definition of “debt service” is the cash that is required to cover repaying interest and principal for a debt during a set period of time. Borrowers and lenders use the Debt Service Coverage Ratio to measure the ability to repay the annual debt service compared to the net operating income generated by the property. It’s one measurement that helps determine what maximum loan amount you can get. It can help you and a lender understand whether a property generates enough income to cover the cost of a new loan.