The main aim of this paper is to examine the consequences of International (Accounting) Financial Reporting Standards/IFRS-IASB and deferred taxation for banks in Eurozone area. The analysis used data from Annual Reports of four systemic Greek banks, which control around 95 percent of the sector's assets and 90 percent of total deposits. The results suggests that increasing banks' losses may improve their capital adequacy. The paper is organized as follows: in the next section we briefly present interactions between IASB and BASEL aiming at preventing banking and accounting problems at international level during the last decades. This is followed by the comparative analysis of banking supervision accords and the presentation of International Accounting Standard 12: Income Taxes. The research methodology, the data sources used in the analysis and research results are presented and discussed in section four. Last section summarizes the conclusions and presents further opportunities for research.