Axis Bank has mandated JPMorgan, Deutsche Bank and Goldman Sachs to arrange a roughly $1.25 billion share sale, two sources with direct knowledge said.
The private sector lender is raising the money to beef up its capital base as it expects robust credit demand on the back of an economic revival in Asia's third largest economy, the sources who declined to be named said.
The share sale is expected to open in late September or early October, provided markets remain buoyant, they said.
"Once the shareholders' approval is received for the share sale, we should be able to quickly finish the investor meets and launch the offer," one source said.
Axis Bank did not have immediate comment.
Shareholder approval for the sale of up to 71.4 million shares either by private placement to institutions or through global depositary receipts is expected in early September, the sources said.
The type and size of the offering will be decided in September, they said.
The bank said this week a part of the issue would be offered to some of its founders, including state-run Life Insurance Corp, to help them maintain their stake levels.
An economic revival has made companies revisit expansion plans, fuelling demand for loans and prompting banks to raise capital.
Axis Bank had capital adequacy ratio of 15.3 percent as at June, well above the regulatory requirement of 9 percent and the central government's comfort level of 12 percent.
It last raised equity capital through a simultaneous offering of GDRs, private placement to institutions and founders worth 45.3 billion rupees in July 2007.
Shares in Axis Bank, which has a market value of $6.6 billion, have jumped 72.5 percent this year to 870.30 rupees, outpacing the main index that has risen around 60 percent.
Indian companies have raised almost $10 billion by selling shares so far this year, surpassing the money raised in 2008, helped by a more than 90 percent rise in the benchmark index from its March lows.
A clutch of Indian firms including at least a dozen state-run companies are eyeing share sales to fund expansion in Asia's third largest economy.