Debt Structure

We review the literature on debt structure, which is a central element in a firm's capital structure. We first survey both theoretical and empirical research pertaining to debt characteristics-maturity and priority-and debt types-bank loans, corporate bonds, credit lines, commercial paper, and capital leases. We then present comprehensive empirical evidence on public US firms' debt structure over the period 2002-2018, highlighting that more than three-quarters of US firms concentrate their borrowing in one debt type, and offer some suggestive explanations for the observed pattern. Finally, we discuss directions for future research, including a better understanding of debt structure choices by non-US firms and by private firms, the cross-sectional and temporal variations in debt structure, the corporate policy implications of firms' debt structure choices, and the interaction between types of assets and debt structure.