How to build a diversified portfolio

Start with allocation, not stock picks

Decide the split between equity, debt and cash before choosing any company. That single decision drives most of your long-run outcome and all of your ability to sleep during a drawdown.

Your horizon sets the split. Money needed within three years does not belong in equities.

How many stocks

Most of the benefit of diversification arrives by around 20 holdings. Beyond 40, you own an expensive index fund and cannot track any of it properly.

Fewer than 10 concentrated positions is a legitimate strategy, but only if you genuinely know each business.

Correlation, the hidden trap

Owning ten stocks that all depend on the same interest-rate cycle is one bet written ten ways. Check what actually drives each holding's revenue.

Spread across sectors, and where possible across currencies and geographies — the NSE, Nasdaq and LSE do not move in lockstep.

Sizing and rebalancing

A common rule is to cap any single position at 5–10% of the portfolio at purchase, and any sector at around 25%.

Rebalance on a schedule — annually, or when a position drifts more than a set percentage from target. Scheduled rebalancing forces you to trim winners and add to laggards, which is exactly what emotion resists.

Frequently asked questions

How many stocks should a beginner own?

Around 15 to 25 across several unrelated sectors, or a broad index fund plus a handful of individual convictions.

How often should I rebalance?

Once or twice a year is enough for most investors. More frequent rebalancing adds costs without adding much benefit.

Does diversification prevent losses?

No. It reduces the impact of any single failure, but in a broad market decline most holdings fall together.