Concluding remarks
This study examines whether book-tax differences (BTDs) are associated with private borrowing costs. Specifically, we examine whether total, permanent, and/or temporary BTDs relate to two separate proxies for private debt costs, interest rate spread and security requirements. We find that costs of private debt are generally increasing in the levels of and variability in temporary BTDs, but not permanent ones. We also find that the relation between BTDs and private debt costs holds for BTDs of both signs (i.e., positive and negative) and is stronger where lenders have especially high stakes in the private loan market (i.e., more experience and higher incentive to monitor). Further, our results suggest that tax planning impacts the association between BTDs and loan costs; the positive relation documented in our main results is mitigated for firms that engage in heavy tax planning activities. Overall, our results are consistent with BTDs raising concerns about earnings quality, resulting in a perception on the part of lenders of increased borrower risk and thus higher borrowing costs. Our findings further indicate that earnings quality-related concerns about risk are alleviated if the BTDs are generated by a high-tax-planning firm. Notwithstanding recent research documenting (mixed) evidence of a direct link between tax avoidance, measured using BTD-based proxies, and private loan costs (Hasan et al., 2014; Kim et al., 2010), our study provides evidence in a private debt setting that BTDs contain risk-relevant information beyond tax avoidance itself. Our findings on the interaction between book-tax differences and private debt costs contribute to our understanding of the role of tax and financial reporting in private debt contracting and to the growing literature examining the potential economic effects of the information (and related uncertainty) contained in BTDs. Our study extends and complements Ayers et al. (2010), which focuses on credit ratings (i.e., public debt). We provide evidence on the manner in which book-tax differences relate to costs of private debt, and together with Ayers et al. (2010), our results show that the information (and related uncertainty) contained in BTDs can impact debt markets on multiple dimensions.