Large, mid or small cap: how SEBI actually defines the fund you own (rank 1-100, 101-250, 251+)
SEBI's 2017 circular defines large, mid and small cap funds by a company's rank in the full market-cap list: 1-100, 101-250 and 251 onwards. Here is what that means for risk and tax.
When you buy a "large cap" or "small cap" mutual fund in India, you are not relying on a vague marketing label. Since the SEBI circular SEBI/HO/IMD/DF3/CIR/P/2017/114 dated 6 October 2017 on Categorization and Rationalization of Mutual Fund Schemes, the words "large", "mid" and "small" cap have a precise, rules-based meaning: they are defined by a company's rank in a list of all listed Indian companies sorted by full market capitalisation. Rank 1 to 100 is large cap, rank 101 to 250 is mid cap, and rank 251 onwards is small cap. Everything else about how these funds behave, tax and volatility included, flows from that single ranking rule.
This matters because two funds with very different risk profiles can sit in the same portfolio without an investor realising it. A large cap fund must keep at least 80% of its assets in the top 100 companies, while a small cap fund must keep at least 65% in companies ranked 251 and below. That 80-versus-65 split, combined with the identical 12.5% long-term capital gains rate that applies to all three since 23 July 2024, is exactly why understanding SEBI's definitions is the first step before you run any SIP calculator projection.
Side-by-Side Comparison
The 2017 circular created five market-cap-based equity categories, but the three that most investors actually compare are Large Cap, Mid Cap and Small Cap funds. The table below sets out the exact SEBI definition, the minimum allocation mandate and the core trade-off for each.
| Attribute | Large Cap Fund | Mid Cap Fund | Small Cap Fund |
|---|---|---|---|
| Underlying company rank (by full market cap) | 1st to 100th | 101st to 250th | 251st onwards |
| Minimum allocation to that segment (SEBI mandate) | 80% | 65% | 65% |
| Governing rule | SEBI circular 6 Oct 2017 | SEBI circular 6 Oct 2017 | SEBI circular 6 Oct 2017 |
| Relative volatility | Lowest of the three | Higher than large cap | Highest of the three |
| Liquidity of underlying stocks | Highest | Moderate | Lowest |
| Schemes per AMC | One (with stated exceptions) | One | One |
Three points on this table deserve emphasis. First, the ranking is based on full market capitalisation (total shares multiplied by price), not free-float, so the cut-offs at rank 100 and rank 250 are calculated on the entire universe of listed companies. Second, the Association of Mutual Funds in India (AMFI) publishes and updates the ranked list of companies every six months, so a company can migrate from mid cap to large cap (or the reverse) at a June or December reset, forcing funds to rebalance. Third, SEBI allows only one scheme per category per AMC (with limited stated exceptions), which is why you will rarely see a single fund house running three near-identical small cap funds.
The remaining 20% of a large cap fund, and up to 35% of a mid cap or small cap fund, can be held outside the mandated segment, in cash, debt or stocks of other capitalisation bands. This flexibility band is where active managers try to add alpha, and it is also why a "large cap" fund can carry a slice of mid cap risk you may not expect. Always read the scheme's actual portfolio disclosure rather than trusting the label alone; you can sanity-check the compounding assumptions in a lumpsum calculator once you know the true risk mix.
How SEBI Draws the Line at Rank 100 and Rank 250
Before the October 2017 circular, fund houses defined "large cap" and "small cap" however they liked, which made two funds with the same name genuinely incomparable. SEBI's fix, effective for existing schemes that were given until roughly mid-2018 to comply, was to anchor every definition to a single, externally published ranking so the market capitalisation bands could never be gamed.
The mechanics are worth spelling out. AMFI takes the full list of listed companies, sorts them by average full market capitalisation over the preceding six months, and assigns ranks. The 100th company on that list is the boundary of the large cap universe; the 101st to 250th companies form the mid cap band; and the 251st company onwards is small cap territory. Because the list refreshes twice a year, the identity of "the 100th company" changes over time even though the rank cut-off of 100 never does.
This rank-based system has a subtle consequence: the small cap universe from rank 251 is enormous, running into hundreds of companies, whereas the large cap universe is capped at exactly 100 names. That is why small cap funds carry markedly higher volatility and lower liquidity, since they fish in a deep but thinly traded pool. It is also why SEBI, in a March 2024 stress-testing push, asked small and mid cap funds to disclose how quickly they could liquidate portions of their portfolios, a direct acknowledgement of the liquidity gap the rank-251 rule creates.
Tax Treatment
All three fund types are equity-oriented schemes, meaning they hold at least 65% of assets in domestic equity, and therefore share an identical tax framework. The distinction that matters for tax is holding period, not market-cap band. The rates below follow the Budget 2024 regime effective 23 July 2024.
| Tax head | Holding period | Rate | Key relief |
|---|---|---|---|
| Short-Term Capital Gains (STCG) | 12 months or less | 20% | None |
| Long-Term Capital Gains (LTCG) | More than 12 months | 12.5% | First Rs 1,25,000 of gains per financial year exempt |
For any of the three categories, a redemption within 12 months is taxed as STCG at a flat 20% on the entire gain. Hold for more than 12 months and the gain qualifies as LTCG, taxed at 12.5% only on the portion above the annual exemption of Rs 1,25,000. There is no indexation benefit on equity funds, so the 12.5% applies to the nominal gain. On top of the base tax, a 4% health and education cess applies, and surcharge may apply for high-income investors, though surcharge on equity LTCG is capped at 15%.
A worked example makes the exemption tangible. Suppose you redeem a small cap fund after three years with a total long-term gain of Rs 3,00,000 in FY 2025-26. The first Rs 1,25,000 is exempt, leaving Rs 1,75,000 taxable at 12.5%, which is Rs 21,875 before cess. The same arithmetic applies whether the fund was large, mid or small cap, because SEBI's capitalisation label has no bearing on the Income Tax Act's treatment of an equity-oriented scheme. If you invest through an ELSS tax-saver instead, note that the three-year lock-in changes when the LTCG clock can be crystallised; our ELSS calculator models that lock-in explicitly.
Who Should Pick Which
Because the tax treatment is identical, the choice between large, mid and small cap is entirely a question of risk appetite, time horizon and the role the fund plays in your portfolio, not of after-tax efficiency.
Large cap funds suit investors who want equity participation with the lowest volatility SEBI's categories allow. With 80% locked into the top 100 companies, these funds move closest to the broad benchmark and are the natural core for a first-time equity investor or someone within five years of a goal. If capital preservation matters more than chasing the last few percentage points of return, the rank-1-to-100 mandate is the defensive choice. Investors comparing this against a benchmark index fund should weigh the expense ratio difference, since active large cap funds have historically struggled to beat their index net of costs.
Mid cap funds occupy the middle ground, with a 65% mandate to companies ranked 101 to 250. These are businesses that have outgrown the small cap stage but have not yet reached the top 100, and they suit investors with a seven-year-plus horizon who can tolerate sharper drawdowns in exchange for higher growth potential. A mid cap allocation makes most sense as a satellite holding of perhaps 15% to 25% of an equity portfolio rather than the core.
Small cap funds, anchored to rank 251 onwards, are the highest-risk, highest-liquidity-risk option. They demand a ten-year-plus horizon and the emotional discipline to hold through deep corrections, given the thin trading in the underlying universe that SEBI's 2024 stress tests highlighted. A staggered SIP into small caps, rather than a single lump sum, is the standard way to manage the entry-timing risk in such a volatile segment. Treat small caps as a return-enhancer capped at a modest share of your total equity, never as the foundation.
For most investors, the practical answer is a blend rather than a single pick: a large cap core for stability, a mid cap satellite for growth, and a small, disciplined small cap sleeve for the long horizon. Rebalance at each AMFI June and December list reset, because a stock migrating between bands can quietly shift your fund's true risk profile.
FAQ
What exactly is the difference between large cap, mid cap and small cap as per SEBI?
Under SEBI circular SEBI/HO/IMD/DF3/CIR/P/2017/114 dated 6 October 2017, companies are ranked by full market capitalisation. Rank 1 to 100 are large cap, rank 101 to 250 are mid cap, and rank 251 onwards are small cap. A large cap fund must hold at least 80% in large caps; mid cap and small cap funds must each hold at least 65% in their respective segments.
Who decides which company is large, mid or small cap?
AMFI (the Association of Mutual Funds in India) publishes and updates the ranked list of companies every six months, based on average full market capitalisation. Fund houses must use this list, so no AMC can define the bands on its own. The list is available on amfiindia.com.
How often can a fund's holdings change category?
Because AMFI refreshes the ranked list twice a year, a company can move from mid cap to large cap, or from small cap to mid cap, at a June or December reset. When that happens, funds may need to rebalance to stay within their mandated minimum allocation of 80% (large cap) or 65% (mid or small cap).
Are large, mid and small cap funds taxed differently?
No. All three are equity-oriented schemes holding at least 65% in equity, so they share the same rules. Gains on units held 12 months or less are STCG taxed at 20%; gains on units held longer are LTCG taxed at 12.5% above the Rs 1,25,000 annual exemption, with no indexation, under the Budget 2024 regime effective 23 July 2024.
Can one AMC run multiple large cap funds?
Generally no. SEBI's 2017 rationalisation permits only one scheme per category per AMC, with limited stated exceptions such as index funds, exchange-traded funds, sectoral or thematic funds, and funds of funds. This is why fund houses had to merge or reposition overlapping schemes after the circular took effect.
Is a small cap fund always riskier than a large cap fund?
By SEBI's design, yes, in terms of volatility and liquidity. The small cap universe from rank 251 spans hundreds of thinly traded companies, whereas the large cap universe is capped at the top 100. SEBI's March 2024 stress-testing requirement for small and mid cap funds was a direct response to this liquidity gap.
What is the minimum holding period to get the lower tax rate?
For all three equity fund categories, you must hold units for more than 12 months to qualify for the 12.5% long-term capital gains rate. Redeem within 12 months and the entire gain is taxed as short-term capital gains at 20%, regardless of whether the fund is large, mid or small cap.