Purpose: The purpose of this thesis is to investigate the relationship between audit quality, with a specific focus on auditor size and audit fees, and the cost of debt and access to debt for medium-sized privately held enterprises in Sweden. Additionally, we seek to explore how family firms moderate these relationships.   Theoretical perspective: This paper combines signaling theory and agency theory to theorize how Big-4 classifications of audit firms and audit fees signal audit quality and different levels of agency cost of debt to creditors. Further, it explores the moderating effect of family firms using socioemotional wealth theory alongside agency theory.   Method: This study is based within the positivistic paradigm, employing a deductive approach. The study uses a quantitative methodology, gathering data from 463 medium-sized privately held enterprises in Sweden. The empirical data is analyzed using multiple linear regressions, with the moderating effects of family firms.    Findings: The findings of this study suggest that firms engaging Big-4 audit firms do not experience lower costs of debt nor improved access to debt. However, audit fees demonstrate a positive relationship with both the cost of debt and access to debt. Further, the study indicates that family firms do not have a moderating effect on these relationships.