The 30-share BSE index after commencing higher, surged further to breach the 25,000 mark once more. It hit the day's high of 25,044.06, before settling 213.68 points, or 0.86 per cent higher, at all-time closing high of 25,019.51.
The rally was powered by shares of metal, oil and gas, power, PSUs, FMCG and IT.
The gauge has now surpassed its previous closing high of 24,858.59 on Tuesday. Its intra-day all-time high remains 25,375.63 hit on May 16.
The 50-share NSE Nifty climbed 71.85 points, or 0.97 per cent, to close at a new peak of 7,474.10, breaching previous record closing high of 7,415.85 on Tuesday. Yesterday, both the Sensex and the Nifty fell.
There is growing speculation that the European Central Bank (ECB) will ease monetary policy later today to support a fragile recovery, said traders.
Metal and oil&gas prices usually go up after an economic stimulus on hopes some funds will come into such assets.
Sentiment was also bullish following foreign funds inflow on continued optimism about a revival in Indian economy, they added. Metal stocks - Sesa Sterlite Ltd and Tata Steel - led the surge helping Sensex end above 25,000-mark for the first time.
Investors were seen accumulating blue-chip stocks on hopes that the government would announces industry-friendly measures in its first budget in July.
"We may see Sensex levels at 30,000 before budget," said Motilal Oswal, CMD, Motilal Oswal Financial Services.
Foreign Institutional Investors (FIIs) bought shares worth a net Rs 192.56 crore in yesterday's trade as per provisional data from the stock exchanges.
Among sectoral indices, the BSE Metal index gained the most by surging 3.33 per cent as Sesa Sterlite Ltd, SAIL, Hindalco and Tata Steel gained in 3-7 per cent range.
The BSE Oil and Gas index emerged second best performer by rising 1.96 per cent, followed by Power (1.96 per cent) and FMCG (1.49 per cent). However, the BSE Banking index ended 0.39 per cent lower due to profit-taking.
Dipen Shah, Head- Private Client Group Research, Kotak Securities: The benchmark indices ended at another record high today. The mid-cap index continued to outperform the benchmarks with several shares in that index witnessing sizeable buying. The optimism on the budget as well as future growth remains high. Participants are ready to give higher valuations to beaten down mid-cap stocks, which are perceived to witness relatively higher growth, once the recovery sets in. We see the monsoon progress and the budget to be the two important triggers for the markets. We feel that, a progressive budget as well as other reform initiatives will likely lead to continued outperformance of Indian indices v/s emerging market peers.