SUMMARY
This study empirically examines how the adoption of IFRS affected the reported profits and effective tax rates of firms by analyzing consolidated financial statements and separate financial statements. Firms that adopted IFRS in 2011 were required to disclose consolidated financial statements and separate financial statements in both K-IFRS and K-GAAP for this period. We conjecture that there will be a difference in the reported profits and effective tax rates between the financial statements that adopt the two different accounting standards. This study will provide policy implications with regards to the recent IFRS adoption and the use of accounting standards.The findings of this study are as follows. First, we find that the effective tax rate and corporate tax expenses decreased after the adoption of K-IFRS from K-GAAP. Earnings Before Tax (EBT) and net income also decreased when reported in K-IFRS. When we divide the total sample into the listed firms and KOSDAQ firms, we found a significant difference between the accounting standards in the total sample and listed firms, but did not see such a difference in KOSDAQ firms. In addition, results from the analysis of separate financial statements were analogous to those from consolidated financial statements. Additional analyses examined the effect of the early adoption of IFRS, but a significant influence due to early adoption was not found in consolidated financial statements from both parametric and non-parametric tests. However, the effective tax rate did decrease in the separate financial statements of firms that adopted K-IFRS earlier.The implementation of K-IFRS (changes in accounting standards) has made the managerial performance of firms accounted for in the Equity Method to be reflected in EBT and net income. This entailed an increase (or decrease) in the Equity Method profit, which in turn increased reported profits and decreased effective tax rates. In other words, the total increase of reported profits in consolidated financial statements can be attributed to subsidiary companies. However, the adoption of IFRS also reduced the tax burden, which is considered to be the motivation for firms to adopt IFRS in advance.This article attempts to provide policy implications with regards to the adoption of new accounting standards and its influence on the corporate tax expenses and effective tax rates in listed firms and KOSDAQ firms.