Effects of Firm Size on the Relationship between Disclosure and Cost of Equity Capital in Companies Listed in Tehran Stock Exchange

This study investigates the effects of firm size on the relationship between disclosure and cost of capital equity. The purpose of this study is to provide a formal test on the claim that states large firms benefit from disclosure، more than small firms. In this study، we have used a sample of 107 firms listed in the Tehran Stock Exchange in the period 1385 to 1389. Multiple regression analysis is used to test the claim hypothesis. The results showed that firm size moderates the relationship between disclosure and cost of equity. The result revealed a significant negative relationship between disclosure and cost of equity for large firms and a non-significant relationship for small firms.