Position Sizing and Concentration Risk

How much of your portfolio should any single stock represent? There's no universal rule, but consider your confidence, the size of the company, and its volatility. A position in Reliance Industries (large-cap, low-volatility) might safely be 5-10% of your portfolio. A position in a micro-cap or high-volatility stock should be smaller—1-3%. If you're not willing to lose 3% of your portfolio on a stock, don't own 10% of it.

Concentration creates optionality for outperformance but also catastrophe risk. A portfolio with 10% positions across 10 different stocks is undiversified; a downturn in a couple of them could cut your wealth significantly. A portfolio with 1-2% positions across 50 stocks is over-diversified; you won't beat the index much. 3-5% positions across 15-20 stocks is a good middle ground for active investors: you have real conviction without betting the farm on any single idea.

Early-stage investors often accumulate concentration unintentionally: a position that was 2% of a Rs 10 lakh portfolio becomes 8% of a Rs 15 lakh portfolio (if it grows 50% while the portfolio grows 20%). Many investors have regretted this after a concentrated position crashed. The fix is to trim holdings that become oversized or to add new capital to smaller positions to maintain balance.

Concentrated portfolios amplify wins and losses. If you hold 5 stocks and one quadruples while the others double, that one now dominates your returns and risk. This is fine if you have high conviction in the pick, but most investors underestimate correlation—in downturns, even dissimilar stocks often fall together. Maintain some constraint on position size to ensure that no single mistake derails your long-term plan.

• Match position size to conviction and volatility.
• 3-5% per position is a reasonable range for active investors.
• Trim winners that grow too large; add to laggards.
• Concentration magnifies both wins and losses.