The A regulated electronic marketplace in Mumbai where buyers and sellers trade shares and other securities at publicly visible prices. Read the full meaning of NSE (National Stock Exchange) Indices factsheet dated 30 October 2026 still describes the Nifty Alpha 50 Index as a set of 50 securities that are both chosen and weighted by alpha, and the index is reviewed every quarter. Alpha here means the return a stock has delivered over and above what its market movement would explain.
For each review, the data used covers six months and ends on the last trading day of February, May, August and November. The next review will therefore draw on data ending on the last trading day of November 2026. Alpha of the eligible securities is worked out from trailing one year prices, adjusted for corporate actions.
Alongside this, there is a Nifty Alpha 50 Total Returns Index, which is the variant of same basket.
How the 50 stocks get in
The selection begins with a candidate pool. The candidate pool is made of companies ranked within the top 300 by average free-float market capitalisation and average daily turnover, with a listing history of at least 1 year and trading on every day of the last year.
From this pool, only the securities with positive alpha are eligible at each review. Stocks that have delivered less than their market movement would explain are left out at this stage.
Liquidity and market capitalisation screens are applied next, so the basket stays investable and can be replicated by funds tracking it. The final 50 are then chosen on the basis of their alpha values, and a replacement pool supplies the next highest alpha names whenever a slot opens.
Weights follow alpha
In the Nifty Alpha 50 Index, the weight of each stock is set in proportion to its alpha, so the stock with the highest alpha gets the largest weight in the basket. A company's size does not decide its place here, which is different from the way many investors expect an index to work.
The 2019 NSE methodology document says index uses a divisor method, similar to the other NSE indices. Under this method, the index level continues smoothly when the constituents or their weights are changed at a review.
Investors comparing index with funds that track it are therefore looking at weights that move with each quarterly review.
The eligibility details, such as the candidate pool, domicile and listing history, come from an insurer page and not from the official methodology, so the current NSE methodology PDF is the final word.
