This research explores the moderating effect of institutional ownership on the relationship between audit committee attributes and audit report lag. The paper sampled data from 102 Saudi non-financial listed firms from 2012 to 2021. The data was analyzed using a fixed effect regression, while the generalized method of moments approach (GMM) was employed for robustness check. The research finding strongly suggests that the audit committee size may increase audit report lag. In contrast, it was found that audit committee independence and financial expertise may reduce audit report lag. In addition, the interaction effect reveals that the impact of audit committee financial expertise and the committee meetings on reducing audit report lag may be higher as institutional shareholding rises. Thus, the outcome validates the agency theory perspective that the active monitoring of institutional investors may shape firms’ internal governance systems. More importantly, the finding implies that firms should prefer a smaller audit size with a higher ratio of independent directors and financial experts to improve financial reporting quality. They should also embrace institutional shareholding to reduce audit report lag. Thus, lowering audit report lag may mitigate information disparity between firms and prospective investors, reducing agency conflicts and boosting firm value.