HSBC declined to comment.
The newspaper quoted unidentified people involved in the discussions as saying the offer price for the sale had not been set and the deal could still be postponed.
The bank is also expected to announce a cut in its dividend, the FT reported on its Web site www.ft.com.
Investors told Reuters this week they would support a rights issue by the bank, and wanted management to act quickly to remove uncertainty hanging over its share price.
The newspaper said the share sale was underwritten by Goldman Sachs
Goldman Sachs and JPMorgan Cazenove declined to comment.
The deal could set a new record in Britain for a rights issue funded by private investors after Royal Bank of Scotland's
HSBC has traditionally been one of the best capitalized banks in the world and has not raised capital while rivals have scrambled for cash as the credit crisis has deepened.
But some analysts have said that has eroded its competitive advantage and could encourage it to raise funds to protect it against rising bad debts across its businesses.
Shares in HSBC closed 6.8 percent lower on Friday, while European banking stocks <.SX7P> ended the session down 4.8 percent.
(Reporting by Jan Dahinten; Additional reporting by Steve Slater and Douwe Miedema in London; Editing by Ruth Pitchford)