The transaction will be done between June 29 and July 28.
With the LPB share trading at around VND30,000 ($1.30), it is estimated the deal will cost Thaiholdings VND600 billion.
The company was founded by Nguyen Duc Thuy, now the vice chairman of LienVietPostBank, and he owns a 20 percent stake in it.
He previously registered to buy 32.5 million LPB shares. The transaction started early June and will end in early July.