By the time Warren Buffett stepped down as CEO of Berkshire Hathaway at the end of 2025, he had built the company into a more than $1 trillion conglomerate and amassed a personal net worth of about $150 billion, according to the Bloomberg Billionaires Index.
It’s a career that no one seems likely to emulate, but that doesn’t stop people from turning to the Oracle of Omaha for wealth-building advice.
Back in 1999, at Berkshire’s annual meeting, Buffett answered a question from a shareholder about how he would make $30 billion, which was Buffett’s approximate net worth at the time.
“Start young,” Buffett said with a laugh.
“We started building this little snowball on top of a very long hill,” he added. “So we started rolling the snowball very early on. Of course…the nature of compound interest is that it behaves like a snowball.”
Compound interest is a phenomenon in which you earn a profit on your principal and then earn a profit on your principal plus the income, and investment professionals often refer to this as “magic.”
And the “trick” to building a big snowman, Buffett said, “is to have a very long mountain. That means starting very young or living to a very old age.”
Why starting early is the key to building wealth
Buffett went on to say that if you were fresh out of college and had $10,000 to invest, you would build your wealth by finding the same good but undervalued companies you started with.
Buffett has long acknowledged that the average individual investor doesn’t have the time or ability to build a portfolio of individual stocks that can deliver market-beating returns. “In my opinion, the best thing for most people is to own an S&P 500 index fund,” he said at Berkshire Hathaway’s 2021 annual shareholder meeting.
Will that reach $150 billion? Not if you only have $10,000 to invest. But if you play around with compound interest calculators, you’ll see that Buffett’s advice to maximize your runway can have a huge impact on how your wealth grows over time.
Let’s say a 22-year-old college graduate invests $10,000 in a portfolio that earns an average annual return of 8%, and adds an additional $5,000 each year. By the time they reach 95, Buffett’s age, their portfolios will be worth more than $21 million, according to CNBC Make It’s calculations.
If the same investor started investing five years later, the value of the portfolio would drop to less than $15 million. A 10-year lag is less than $10 million.
Of course, none of that is in the same stratosphere as Buffett’s wealth, which he calls “incomprehensible.” However, at the same 1999 meeting, Buffett said that there is little point in having a huge net worth, except to provide oneself with a certain quality of life.
“Beyond a moderate level, funding makes little difference,” he said.
He continued, “If you asked me to trade a significant portion of my net worth for a few years of my life or to be able to do whatever I want to do during that time, I would do it in a heartbeat.”
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