The offer price of 92.25 euros per voting share and 65 euros per preference share will not change during this additional acceptance period, P&G said.
The US consumer goods giant agreed in March to buy 77.6% of voting shares from Wella's majority shareholders. This latest move requires an additional acceptance period under German law to run from June 6 to June 20.
P&G's chief financial officer Clayton Daley said: “Beyond June 20, we are under no obligation to acquire any further shares.
“We will begin to pursue the business objectives we announced on March 18 as soon as the appropriate regulatory approvals are obtained, regardless of the number of shares tendered."