"Don't put all your eggs in one basket." You've heard it a thousand times. But what does diversification actually look like in practice? How many stocks do you need? What about bonds? International?
I made the mistake of owning 3 tech stocks in 2022. When tech crashed, my portfolio dropped 40%. Here's what I learned about building a portfolio that survives bad years.
How Many Stocks Is Enough?
Research says 15-30 stocks eliminate most of the "company-specific" risk (the risk that one company goes bankrupt). Beyond 30 stocks, you're basically tracking the market — which is fine, but you might as well buy an index fund at that point.
If you own fewer than 10 stocks, you're not diversified. If one position is more than 10% of your portfolio, you're making a concentrated bet. That's fine if you know what you're doing. It's gambling if you don't.
Diversify Across Sectors
Owning 20 tech stocks isn't diversification — it's tech exposure in 20 packages. Real diversification means owning companies in different industries that react differently to economic conditions.
| Sector | Why Own It | Example ETF |
|---|---|---|
| Technology | Growth driver, high returns | QQQM, VGT |
| Healthcare | Recession-resistant, aging population | XLV |
| Consumer Staples | People buy food and soap in any economy | XLP |
| Financials | Benefit from rising interest rates | XLF |
| Energy | Hedge against inflation, different cycle | XLE |
| Real Estate | Income generation, inflation hedge | VNQ |
International Diversification
US stocks have outperformed international stocks for most of the last 15 years. That doesn't mean they always will. Owning international stocks protects you from the risk that the US market underperforms for a decade — which has happened before (2000-2009).
A common rule: allocate 20-40% of your stock portfolio to international. VXUS or IXUS are the go-to ETFs.
Bonds: Do You Need Them?
Bonds reduce volatility but reduce returns. How much you need depends on your timeline:
- 20+ years from retirement: 0-10% bonds
- 10-20 years: 10-20% bonds
- 5-10 years: 20-40% bonds
- In retirement: 40-60% bonds
A simple bond ETF like BND or AGG gives you broad exposure to US bonds.
A Simple Diversified Portfolio
You can build a well-diversified portfolio with 3-4 ETFs:
- VTI — Total US stock market (60%)
- VXUS — Total international stock market (20%)
- BND — Total US bond market (10% if young, more if old)
- VNQ — Real estate (10%)
That's 10,000+ stocks and 10,000+ bonds in 4 tickers. Rebalance once a year. Done.
Use our Compound Interest Calculator to see how a diversified portfolio grows over 20+ years compared to cash.