Top-10 firms gain ₹3.65 lakh crore in market cap as Sensex rallies 3%
Synopsis
In a single week, nine of India's ten most-valued companies collectively added ₹3.65 lakh crore in market capitalisation, with TCS alone contributing over ₹1 lakh crore of that gain. The surge came as the Sensex posted its sharpest weekly rally in recent memory — a signal of broad institutional buying across IT, telecom, banking, and energy sectors.
Key Takeaways
Nine of India's top-10 most-valued firms collectively gained ₹3.65 lakh crore in market cap during the week ended 18 October 2026 .
TCS was the biggest gainer, adding ₹1,08,542.63 crore to reach a market cap of ₹8,91,134.96 crore .
Bharti Airtel added ₹61,406.53 crore ; Infosys gained ₹55,893.05 crore .
Reliance Industries remains India's most valuable listed company at ₹16,37,437.19 crore .
Larsen & Toubro was the sole loser, shedding ₹9,232.26 crore to ₹4,99,725.06 crore .
The BSE Sensex surged 2,256.94 points ( 3.11% ) and the Nifty50 rose 625.7 points ( 2.77% ) over the week.
Nine of India's 10 most-valued companies collectively added ₹3.65 lakh crore in market capitalisation during the week ended 18 October 2026, riding a sharp rally on Dalal Street that pushed the BSE Sensex up 2,256.94 points, or 3.11%, for the week. The Nifty50 advanced 625.7 points, or 2.77%, over the same period.
Top Gainers of the Week
Tata Consultancy Services (TCS) led the charge as the single biggest wealth creator among the top-10, with its market capitalisation surging ₹1,08,542.63 crore to reach ₹8,91,134.96 crore. Telecom giant Bharti Airtel followed closely, adding ₹61,406.53 crore to push its valuation to ₹11,88,815.45 crore. Infosys rounded out the top three, gaining ₹55,893.05 crore to take its market value to ₹4,71,409.41 crore.
Reliance Holds the Crown, Banks Post Solid Gains
Reliance Industries — which retained its position as India's most valuable listed company — saw its market capitalisation climb ₹53,047.56 crore to ₹16,37,437.19 crore. Private-sector lenders also participated meaningfully in the rally: HDFC Bank added ₹32,379.05 crore to reach a valuation of ₹11,22,628.07 crore, while ICICI Bank gained ₹30,769.95 crore, taking its market cap to ₹10,02,871.44 crore.
Other Movers: Bajaj Finance, LIC, SBI
Bajaj Finance saw its valuation rise by ₹14,786.65 crore to ₹6,11,326.72 crore. Life Insurance Corporation of India (LIC) added a more modest ₹4,933.5 crore, lifting its market capitalisation to ₹5,02,204.82 crore. State Bank of India (SBI) gained ₹3,323.07 crore to stand at ₹8,87,722.84 crore.
L&T the Sole Laggard
Larsen & Toubro (L&T) was the lone outlier among the top-10, shedding ₹9,232.26 crore in market value to close the week at ₹4,99,725.06 crore. The infrastructure and engineering conglomerate bucked an otherwise broad-based rally, though no specific trigger was cited for the divergence.
Current Rankings of Most-Valued Indian Companies
As of 18 October 2026, the pecking order among India's top-10 most-valued listed firms stands as follows: Reliance Industries leads, followed by Bharti Airtel, HDFC Bank, ICICI Bank, TCS, State Bank of India, Bajaj Finance, LIC, Larsen & Toubro, and Infosys. The week's gains underscore continued institutional confidence in India's blue-chip universe, and market participants will be watching whether the momentum sustains into the next earnings cycle.
Point of View
But the concentration tells a sharper story: TCS alone accounted for nearly 30% of the total wealth created, pointing to a market that rewards IT and telecom while infrastructure — as L&T's lone decline illustrates — lags on sentiment. The Sensex's 3.11% weekly jump is healthy but partly mirrors a global risk-on turn rather than domestic earnings momentum. Investors should note that Reliance's ranking at the top masks a relatively modest absolute gain of ₹53,000 crore compared to Airtel's proportional surge — a sign that telecom re-rating may have further to run.
NationPress
18 Oct 2026
Frequently Asked Questions
Which company gained the most market cap among India's top-10 last week?
Tata Consultancy Services (TCS) was the biggest gainer, adding ₹1,08,542.63 crore to reach a market capitalisation of ₹8,91,134.96 crore during the week ended 18 October 2026. It significantly outpaced the second-biggest gainer, Bharti Airtel, which added ₹61,406.53 crore.
Which is India's most valuable listed company as of October 2026?
Reliance Industries is India's most valuable listed company, with a market capitalisation of ₹16,37,437.19 crore as of 18 October 2026. It is followed by Bharti Airtel and HDFC Bank in the top-three ranking.
Why did India's top-10 companies see such a large market cap jump?
The gains were driven by a sharp rally in benchmark indices, with the Sensex climbing 2,256.94 points (3.11%) and the Nifty rising 625.7 points (2.77%) over the week. Positive sentiment on Dalal Street broadly lifted IT, telecom, banking, and energy stocks.
Which top-10 company saw a decline in market capitalisation?
Larsen & Toubro was the only company among the top-10 most-valued firms to record a fall, losing ₹9,232.26 crore to close the week at a market cap of ₹4,99,725.06 crore. It was the sole outlier in an otherwise broad-based rally.
What is the current ranking of India's 10 most-valued companies?
As of 18 October 2026, the ranking is: Reliance Industries, Bharti Airtel, HDFC Bank, ICICI Bank, TCS, State Bank of India, Bajaj Finance, LIC, Larsen & Toubro, and Infosys. The order reflects post-rally market capitalisations as reported for the week.
