The BSE Sensex rose 0.9% in early trade on Thursday, on an upbeat listing for Coal India, the country's largest ever share offering, with strong Asian markets supporting sentiment.
At 9:16 am, the 30-share BSE index was up 0.85% at 20,639.47 points, with all components advancing.
Shares in Coal India, the world's largest coal miner, opened at 295.70 rupees compared with an issue price of 245 rupees, after the Indian government raised $3.4 billion.
The stock extended gains and was trading at 315 rupees.
The 50-share NSE index was up 0.8% at 6,210.70.