Short answer: A smart beta ETF is an exchange-traded fund (a fund that holds a basket of securities and trades on a stock exchange like a share) that tracks an index but uses a rule-based process to choose and weight the securities it holds. A passive ETF tracks a chosen market index and holds each index security in the same proportion as the index, so its aim is to mirror the index’s returns.
Last reviewed: 10 November 2026
At a glance
| Feature | Passive ETF | Smart beta ETF |
|---|---|---|
| What it tracks | A chosen market index | An index, using a rule-based process |
| How it holds securities | Each index security, in the same proportion as the index | Some index securities chosen by factor screens, or all of them at different weights |
| Basis for weights | The index’s own proportions | Factors such as value, momentum, quality, size, dividend yield or volatility |
| Return goal | Mirror the index’s returns | Potential for better risk-adjusted returns, not guaranteed |
How does a passive ETF work?
A passive ETF starts with an index, which is a list of securities chosen by a set rule, such as the Nifty 50. The fund buys each security on that list in the same proportion the index uses. If the index gives a stock 5% of its total, the fund aims to hold about 5% of its assets in that stock.
The fund’s manager does not pick stocks or try to beat the index. The fund’s results are meant to follow the index’s results, minus the fund’s own running costs.
What makes a smart beta ETF different?
A smart beta ETF still tracks an index, so it is rule-based rather than based on a manager’s view of individual companies. Its rules, however, go beyond copying the index’s proportions. It uses a rule-based process to decide which securities to hold and how much weight each one gets.
Most index funds weight companies by market capitalisation, which is the total market value of a company’s shares. Smart beta ETFs assign weights using factors instead of relying only on market capitalisation. A factor is a measurable characteristic of a company. Common examples in this category include value (how cheap a share is relative to the company’s earnings or assets), momentum (how strongly the share price has moved recently), quality (strength of a company’s finances), size, dividend yield (the dividend paid relative to the share price) and volatility (how much the share price moves up and down).
Can a smart beta ETF hold different stocks from its index?
Yes. A smart beta ETF tracking an index such as the Nifty 50 may hold only some of the index’s stocks, choosing them through factor screens. Alternatively, it may hold all the same stocks but give them different weights from the index.
This matters because the fund’s results can then differ noticeably from the index’s results. A fund holding fewer stocks is not a smaller copy of the index. It is a different portfolio built from the index’s universe.
How much does the weighting rule change the result?
The example below uses invented figures for illustration only. It is not based on any real fund or stock.
Suppose an index holds three stocks, X, Y and Z, with market values of ₹600 crore, ₹300 crore and ₹100 crore. A passive ETF holds them in proportion to these values: 60%, 30% and 10%. In one year, suppose X rises 10%, Y is flat and Z falls 20%.
The passive ETF’s return is (0.60 × 10%) + (0.30 × 0%) + (0.10 × −20%) = 6% − 2% = 4%.
Now suppose a smart beta ETF holds the same three stocks but its rule gives them 20%, 30% and 50%. Its return is (0.20 × 10%) + (0.30 × 0%) + (0.50 × −20%) = 2% − 10% = −8%.
The stocks and the year were the same. Only the weights changed, and the result moved from a 4% gain to an 8% loss. A rule can help or hurt, depending on how the market moves.
What are the catches?
The main catch is that the benefit is not guaranteed. Smart beta ETFs are said to have the potential for better risk-adjusted returns than passive ETFs, meaning better returns for the amount of risk taken. But this is a potential, not a promise, and a factor that worked in one period may not work in the next.
Second, the rules are fixed in advance. A value rule keeps favouring cheap shares even when they stay cheap for years. A momentum rule keeps favouring recent winners even when they reverse. The fund follows the rule whatever the market is doing.
Third, a smart beta ETF’s behaviour can differ from the index it tracks. If you compare its results with the Nifty 50 or another index, expect the gap to change over time, sometimes in the fund’s favour and sometimes against it.
Frequently asked questions
Is a smart beta ETF actively managed?
It is not managed by a manager picking stocks on judgement. It uses a rule-based process to choose and weight its holdings, which places it between passive and active funds.
Do smart beta ETFs always beat passive ETFs?
No. They are said to have the potential for better risk-adjusted returns than passive ETFs, but this is not guaranteed.
Do smart beta ETFs always hold every stock in the index?
No. A smart beta ETF may hold only some index stocks, selected through factor screens. It may also hold all of them but give them different weights.
What is the basic difference between a passive ETF and a smart beta ETF?
A passive ETF holds index securities in the same proportion as the index. A smart beta ETF uses factors such as value, momentum or quality to choose or weight its holdings.
Sources and last check
Facts in this article were checked against the sources below on 10 November 2026. Rules and figures can change; check the primary source before acting.
- kotakneo.com (broker education)
- groww.in (broker education)
- zerodha.com (broker education)
This article is general information, not investment advice. MyFinanceBandhu is not a SEBI-registered investment adviser.