The acquisition is part of Spain bank’s earlier agreement with Allied Irish Banks (AIB) to acquire AIB’s stake in Spanish bank.
In addition, Santander also acquired the 50% stake in the BZ WBK Asset Management, which was held by AIB.
The total value of the this transaction is EUR4.13bn.
Bank Zachodni WBK is expected to join Grupo Santander on 1 April, once the takeover offer and the transfer of shares are executed.
Banco Santander chairman Emilio Botin said that with the acquisition of Bank Zachodni, Poland has become a main market for Banco Santander.
"I am confident that Poland will soon become a growth engine for Banco Santander," Botin said.
Santander said following this transaction, which consumes 0.57 points, the core capital of Banco Santander will be 9.1%, up from 8.8%at the close of 2010.
Wroclaw headquartered BZ WBK has 9,840 employees and 527 branches across the country.
