Kotak Mahindra Bank gains as much as 4.2 pct while ING Vysya Bank rises as much as 3.3 pct.
The lenders have extraordinary general meetings later in the day to pass a resolution on their proposed merger.
Kotak in November agreed to buy ING Vysya in record $2.4 bln share deal.
As per swap ratio, every 1,000 shares of ING Vysya, with a face value of 10 rupees each, will fetch 725 shares of Kotak with a face value of 5 rupees each.
The transaction is expected to close in the second half of 2015