One fund can already hold thousands of companies
A fund tracking the MSCI World invests in about 1,400 companies from more than 20 developed countries. One tracking an “all-world” index, such as the MSCI ACWI or FTSE All-World, adds emerging markets and holds over 2,500 companies from around 50 countries.
With one of those funds you already have more diversification than you could get buying shares one by one for your whole life.
Fake diversification
A very common mistake is owning a global fund, an S&P 500 fund and a tech fund, and thinking those are three different bets. They are not: the largest companies in all three are the same (Apple, Microsoft, Nvidia, Amazon…). You hold the same thing three times, with even more weight in a few companies and a single country.
On top of that, around 70% of a developed-markets global fund is already in the US. Add an S&P 500 fund and that share goes even higher.
Simple portfolios that work
One fund: a global index (developed and emerging). It is the simplest option and for many investors it is enough.
Two funds: a global stock index and a bond fund. The bond share decides how much your portfolio moves: more bonds, fewer scares and also lower expected returns.
Three funds: developed, emerging and bonds, so you control the weight of each part yourself.
How to keep your mix without selling
Over time, whatever rises most ends up weighing more than you wanted. The gentlest way to fix it is to send each monthly contribution to the part that has fallen below its target. That way you rebalance without selling and without paying tax on gains.
Frequently asked questions
Are more funds safer?
Only if each fund adds companies, countries or asset types you did not already have. Repeating the same indexes adds fees and complexity, not safety.
Do I have too much in the US?
That is your call, but it is worth knowing. With a developed-markets global fund, around 70% of your money depends on that country (a bit less if it includes emerging markets).
How often should I check my portfolio?
Once a year is usually enough. Looking every day does not improve it and makes you more tempted to tinker.
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Educational content. Not financial advice: past returns do not guarantee future ones.