Mutual Fund Portfolio Overlap 2026: How to Check If Your SIPs Are Actually Diversified
By Nitish Bharadwaj · Published Aug 4, 2026 · 7 min
Owning multiple mutual funds doesn't automatically mean diversification — a large-cap fund, a flexi-cap fund, and an index fund from three different AMCs can share 50-70% of their top holdings, since all three often draw from the same universe of large, liquid stocks. This guide explains what portfolio overlap actually measures, how to check it using free tools built on AMFI-disclosed factsheets, what overlap percentage should worry you, and how to restructure an over-lapped SIP portfolio without triggering unnecessary capital gains tax.
Five SIPs running across five different AMCs looks like diversification on a statement, but pull up the actual portfolio holdings and a familiar pattern shows up: HDFC Bank, ICICI Bank, Reliance Industries, and Infosys sitting inside three or four of those five funds, often as top-10 holdings in each. This is portfolio overlap, and it's the reason many investors who think they're spreading risk across funds are really paying multiple expense ratios to hold one concentrated bet on the same twenty large-cap stocks. Here's how overlap actually gets measured, how to check yours for free, and what counts as diversification worth paying for.
What Portfolio Overlap Actually Measures
Overlap isn't simply counting how many stock names two funds share — a fund holding 2% in a stock and another holding 9% in the same stock 'overlap' on that name, but the overlap percentage weights both allocations to reflect how much of your actual money is exposed to the same company through both funds. The standard calculation sums the lower of the two weights for every common holding across the two portfolios: if Fund A holds 8% in HDFC Bank and Fund B holds 6%, that stock contributes 6 percentage points to the overlap score, since 6% is the smaller of the two. Add this up across every shared holding, and you get a single overlap percentage between the two funds.
Where Overlap Sneaks Into a 'Diversified' Portfolio
Overlap shows up most in category pairings that look different by name but draw from the same pool of stocks. A large-cap fund and a flexi-cap fund frequently run 40-60% overlap, since most flexi-cap mandates still tilt heavily toward large caps even with the freedom to go elsewhere. Two ELSS funds from different AMCs often overlap 30-50%, because the tax-saving mandate still pulls from the same benchmark-heavy universe most fund managers default to. The overlap that catches investors most off guard is between an index fund and an 'active' large-cap fund that has quietly become a closet indexer — many active large-cap managers stay close to the Nifty 50 rather than deviate meaningfully, and overlap in these pairs can run past 70-80%. Our flexi-cap vs multi-cap comparison and index fund vs active fund data both go deeper into why these categories end up holding similar stocks despite different mandates.
How to Check Overlap Yourself
You don't need a paid subscription to check this. Every AMC publishes a monthly portfolio factsheet listing full holdings, and free tools like Value Research and Advisorkhoj offer a dedicated overlap calculator — you pick two (or more) scheme names, and the tool cross-matches the latest disclosed holdings to output a single overlap percentage along with the specific stocks driving it. Running this check takes under two minutes per fund pair and is worth doing any time you're about to start a new SIP alongside existing ones, not just as an annual portfolio review exercise.
| Stock | Fund A (Large Cap) weight | Fund B (Flexi Cap) weight | Overlap contribution |
|---|---|---|---|
| HDFC Bank | 9.2% | 7.1% | 7.1% |
| ICICI Bank | 7.8% | 6.4% | 6.4% |
| Reliance Industries | 6.5% | 5.2% | 5.2% |
| Infosys | 5.1% | 4.0% | 4.0% |
| Larsen & Toubro | 3.4% | 2.8% | 2.8% |
Just these five stocks alone contribute roughly 25 percentage points of overlap between two funds an investor might assume are fully distinct — a realistic pattern between many large-cap and flexi-cap pairs on the market today.
What Overlap Percentage Should Actually Worry You
There's no regulator-mandated threshold, but the working rule most fee-only advisors use is straightforward: overlap above 50% between two funds in your portfolio means you're effectively paying two expense ratios to hold what is largely one exposure, and one of the two funds is doing very little independent work for your money. Overlap between 30-50% is a gray zone worth watching but not necessarily fixing — some overlap is unavoidable and even healthy, since the largest, most liquid Indian companies deserve a meaningful weight in most portfolios regardless of which fund holds them. Below 30% generally reflects funds that are genuinely doing different jobs — different market caps, different sectors, or different strategies entirely.
SEBI now applies this logic to one pair of categories directly: since its February 2026 categorisation circular, a fund house running both a value fund and a contra fund must keep their portfolio overlap at 50% or below — see our value funds vs contra funds explainer for how the two strategies differ.
How to Fix an Over-Lapped Portfolio Without a Tax Hit
- Run every pair of funds in your portfolio through an overlap calculator and note which pairs cross 50%
- For each over-lapped pair, keep the fund with the lower expense ratio or the stronger long-term, risk-adjusted track record, and stop fresh SIP contributions to the other rather than redeeming it immediately
- Redirect the freed-up SIP amount toward a category you genuinely don't hold yet — mid-cap, international, or a debt fund — rather than another large-cap-leaning scheme that just recreates the same overlap under a new name
- If you do need to exit an existing holding, use a Systematic Transfer Plan (STP) to move the amount out gradually rather than a lump-sum redemption, spreading the capital gains recognition across months instead of triggering it all in one financial year — our STP guide walks through how this works
The goal isn't to hold the fewest possible funds — it's to make sure every fund in your SIP list is earning its expense ratio by doing something the others aren't. Before adding a sixth or seventh fund to an already large-cap-heavy portfolio, run the overlap check first; our best large-cap fund rankings and best mid-cap fund rankings are a good starting point for finding a genuinely different category to diversify into instead.