Portfolio Overlap: The Hidden Risk When You Own Too Many Funds
Owning more funds does not mean more diversification. When two funds hold the same stocks, you are paying double expenses for a single exposure. Here is how to check and fix it.
A client recently showed me their portfolio: 14 mutual funds, accumulated over 8 years from various advisors and their own research. They felt well diversified. When we ran an overlap analysis, the top 10 stocks appeared in 9 of their 14 funds. They effectively owned one concentrated portfolio, six times over — paying six TERs for a single exposure and congratulating themselves on diversification.
What is Overlap and Why Does it Matter?
Overlap occurs when two funds hold the same stocks. If Fund A and Fund B both hold Reliance Industries, HDFC Bank, and Infosys as their top positions, your combined portfolio is heavily concentrated in those stocks — regardless of how many different funds you own. You have the concentration risk without the benefit of genuine diversification.
Common Overlap Traps
- →Nifty 50 Index Fund + Active Large Cap Fund: 80%+ overlap guaranteed. The index fund holds what the large cap fund mostly holds. One is redundant.
- →Three mid cap funds from different AMCs: Typically 40–60% overlap. The mid cap universe has ~150 stocks; three funds covering it will share most of them.
- →Flexi cap + Large & Mid Cap + Multi Cap: Often high overlap in the large/mid space. All three go wherever they want across market caps, and they largely end up in the same places.
- →Sectoral funds from the same sector: Buying two IT funds or two pharma funds from different AMCs is concentrated, not diversified.
Acceptable Overlap Thresholds
| Overlap Level | Assessment | Action |
|---|---|---|
| Below 30–35% | Acceptable | Funds are adding distinct value; no action needed |
| 35–50% | Monitor | Marginal diversification benefit; review if both funds are needed |
| 50–65% | One fund is redundant | Rationalise — consider consolidating into one |
| Above 65% | Immediate rationalisation needed | Paying double expenses for same exposure |
How to Check Overlap
- →mutualfundoverlap.in — India-specific tool; compare up to 5 funds; shows common stocks and overlap %
- →casanalyser.com — reads your Consolidated Account Statement (CAS) from CAMS/KFintech; gives full portfolio overlap analysis
- →Manual check: Download monthly factsheets from AMC websites; compare top-10 holdings across your funds
AUM and Capacity: A Related Problem
Beyond overlap, fund size matters significantly in smaller market cap segments. When a small cap fund crosses ₹25,000–30,000 crore AUM, it faces a capacity problem: it must deploy so much capital into a limited pool of small cap stocks that it starts moving stock prices against itself when buying or selling. The practical result is that very large small cap funds gradually become mid cap funds in disguise.
SBI Small Cap (₹30,000+ Cr) closed to lumpsum investments — actually a healthy sign that management is protecting existing investors from AUM dilution. Nippon Small Cap (₹60,000+ Cr) remains open but shows increasing mid cap holdings. The category mandate starts slipping under AUM pressure.
AUM guidelines for equity fund selection
Small cap: Flag if AUM exceeds ₹25,000–30,000 Cr; significant concern above ₹50,000 Cr Mid cap: Flag above ₹60,000–80,000 Cr Large cap: AUM is much less of a constraint (deep liquid market) Check AUM trends: A fund attracting ₹5,000–10,000 Cr per month after media coverage is a concern — that influx of capital must be deployed immediately, often at higher prices
The Right Number of Funds
Portfolio size should dictate fund count, not the other way around. Below ₹5 lakh: 1–2 funds is entirely sufficient — a flexi cap fund covers the equity universe; a BAF adds downside protection. At ₹20–100 lakh: 3–5 funds covering distinct categories (large, mid, debt, perhaps gold) adds genuine diversification. Above ₹1 crore: 5–8 funds can add factor exposure, international diversification, and specific category plays.
The test is simple: each fund must play a role that no other fund in the portfolio already plays. If you cannot articulate what distinct exposure a fund adds, it is probably creating overlap rather than diversification.
This article is for educational purposes only. It does not constitute investment advice. Mutual fund investments are subject to market risks — please read all scheme-related documents carefully before investing.