"The EBA is currently analysing this emerging practice and will set guidance criteria to correctly assign these elements to either variable or fixed remuneration, so as to ensure that these practices do not lead to a circumvention of the newly introduced cap between the variable and fixed component of remuneration."
In 2012, top bankers received an average of 172,379 euros ($233,341) in base salary and 187,441 euros in bonuses, representing a 31 percent increase in fixed pay and a 30 percent drop in bonuses compared with 2010, according to the EBA.
The watchdog's review will be put to public consultation by the end of 2014 and recommendations will be outlined at the beginning of next year.
Read MoreBye-bye, big bonuses: Hello claw-backs and caps
Bonus caps have been an especially thorny issue in the U.K., which has taken Brussels to the EU's top court arguing the rules will make financial institutions more risky by pushing up basic pay. The British Treasury argued the laws go beyond the EU's power and will threaten London's status as a global financial hub.
Britain had the highest number of bankers in the EU earning over 1 million euros in 2012, according to the EBA, at 2,714.
HSBC became the first lender earlier this year to reveal its plans to circumvent EU pay rules. Top employees at the bank will receive fixed-pay allowances as well as shares to boost their income.
- By CNBC's Arjun Kharpal