Purpose: Prior studies suggest that non-timely 10-Q filings indicate higher potential risks than non-timely 10-K filings. Furthermore, larger audit firms tend to be more risk-averse and conservative about reporting. Inspired by these research streams, this paper aims to investigate the influence of non-timely 10-Q filings on audit fees and the impact of audit firm size on this association. Design/methodology/approach: The cross-sectional audit fee regression model used in this study is similar to that used in prior audit fee research (Simunic, 1980; Francis et al., 2005; Hay et al., 2006; Wang et al., 2013). The model includes the following five major characteristics that would influence auditors’ fee decisions: auditee size (LNAT), complexity (REIVAT, FOREIGN, SEG), financial condition (LOSS, ROA, GROWTH, ZSCORE), special events (ICW, RESTATE, INITIAL, GC) and auditor type (BIG4). To examine the effect of non-timely 10-Q filings on audit fees, the variable NT10Q is included in the audit fee model. Findings: The results indicate that when both non-timely 10-K and non-timely 10-Q filings are included in the regression model, only non-timely 10-Q filings are significantly associated with higher audit fees, suggesting that the presence of non-timely 10-Q filings signals more serious underlying problem than non-timely 10-K filings in the audit fees decision processes. In addition, we find that audit fees for firms audited by Big 4 auditors are 26.4 per cent higher when those firms file non-timely 10-Q reports, whereas there is no significant association between non-timely 10-Q filings and audit fees for firms audited by non-Big 4 auditors. Practical implications: As no attention has been paid to the investigation of the impact of non-timely 10-Q filings on audit fees, with the aim of filling the gap of this specific research area, this study examines the association between non-timely 10-Q filings and audit fees and the influence of audit firm size on this association. Originality/value: The contribution of this paper is threefold: first, it is the first study to examine the association between non-timely 10-Q filings and audit fees. The results show that non-timely 10-Q filings are a better and earlier indicator of audit risk than non-timely 10-K filings. Second, the results reveal that the relationship between non-timely 10-Q filings and audit fees is affected by audit firm size. Specifically, Big 4 auditors tend to charge higher audit fees in the presence of non-timely 10-Q filings, reflecting that they are more sensitive to audit risk than smaller audit firms are. Third, an examination of the quarterly effect of non-timely 10-Q filings on audit fees indicates a stronger effect from the first quarter’s non-timely 10-Q filings, compared to the second or third quarter.
