Is More Diversification Always Better?

Owning ten investments may feel safer than owning three. But what if all ten are doing almost the same thing?

Diversification is about exposure, not counting

The number of investments is a poor measure of diversification. What matters is what risks the total portfolio actually contains.

The difference between investment count and diversification

A portfolio with ten funds can be less diversified than a portfolio with four carefully selected investments if the ten funds have significant overlap or similar risk exposures.

Why do investors keep adding investments?

Investors often add investments because something is performing well, a friend recommended it, a category is popular or they don't want to miss out. Each decision can look reasonable alone while creating an unnecessarily complex portfolio.

Diversification should solve a problem

Ask what risk you are trying to reduce. Diversification can help address concentration, but the solution should match the risk rather than simply increasing the number of holdings.

Asset-class diversification is different from owning many funds

Owning several equity funds may diversify within equity without meaningfully changing the overall equity risk of the portfolio. Asset allocation requires looking at the broader mix of assets.

Diversification doesn't mean owning everything

A portfolio can become so complicated that the investor no longer understands it. Complexity can itself become a problem.

The hidden cost of too many investments

More holdings can mean more to monitor, more overlap, more decisions, more confusion, more temptation to react and less clarity about each investment's purpose.

More diversification can sometimes dilute your portfolio

Adding similar investments can make each holding too small to have a meaningful role without materially improving the portfolio's risk characteristics.

The overlap problem

Different funds can own many of the same companies. Multiple wrappers do not necessarily mean multiple independent sources of risk.

Look through the wrapper

A mutual fund or ETF is a wrapper around underlying securities. The useful question is what the investor is ultimately exposed to.

Diversification can also be geographic

Geographic diversification can introduce different sources of risk and potentially reduce dependence on one market, but it also brings currency, tax, regulatory and market-specific considerations.

Diversification can also be about liquidity

A household can own many assets and still have poor liquidity. Diversification is not only about return patterns; accessibility of money matters too.

Diversification cannot eliminate risk

Diversification can reduce certain concentration risks but cannot eliminate market, economic, inflation, interest-rate, geopolitical, liquidity or behavioural risks.

What about owning different fund houses?

Different fund houses can reduce dependence on one organisation, but if their underlying holdings are similar, the diversification benefit may be smaller than expected.

What about different mutual fund categories?

Different categories can provide different exposures, but category labels alone do not guarantee useful diversification. Actual exposure, role, risk and goal matter.

The “ten funds” test

Write down every investment and the job it performs. If you cannot explain an investment's role clearly, it deserves review.

The “remove one” test

Ask what meaningful diversification would be lost if a particular investment were removed. If the answer is not much, investigate why it was added.

The “one portfolio” test

Imagine all holdings on one page. Check equity, debt, liquidity, concentration, repeated companies, repeated roles and what would happen during a major market decline.

Diversification vs asset allocation

Asset allocation describes the mix across asset classes. Diversification describes how exposure is spread within and across investments. Both matter.

What about gold?

Gold can have a role in some portfolios, but owning it does not automatically make a portfolio diversified. Its allocation should have a purpose.

What about real estate?

A primary home and an investment portfolio serve different purposes. Real estate can be a major part of household wealth but may have different liquidity and diversification characteristics.

Don't confuse diversification with safety

A portfolio with twenty investments can still be risky, while a portfolio with five can be appropriately diversified. The number does not determine risk.

What this does NOT mean

More diversification is not automatically bad. It does not mean owning only one fund, that fewer investments are always better, or that every portfolio should have the same number of investments. The point is to own things deliberately.

A better diversification framework

Before adding an investment, ask: What risk does this reduce? What role does it play? What does it overlap

with? Does it change my overall allocation? Would my portfolio be materially different without it?

North Horizon perspective

Diversification is not a competition to see who can own the most investments. The objective is to manage concentration without making the portfolio unnecessarily complicated.

A simple rule to remember

Before adding another investment, ask: 'Am I diversifying my portfolio — or just increasing the number of things I own?'

The North Horizon takeaway

Diversification is about spreading risk intelligently, not collecting investments. A well-structured portfolio should be understandable: what you own, why you own it, what risk it carries and what goal it supports.