Warren Buffett's annual salary has been $100,000 for 40 years. Here's a look at the billionaire investor's unique compensation.

• Warren Buffett's annual salary has been $100,000 for the past 40 years.
• Berkshire Hathaway spends triple that amount on his security each year.
• Buffett owns about $100 billion of Berkshire stock and lives modestly.
• See more stories on Insider's business page.

Warren Buffett is a legendary investor, leads one of the world's biggest companies, and has ranked among the world's wealthiest people for decades. Yet he earns a modest annual salary of $100,000 — and hasn't had a pay rise in 40 years, SEC filings show.

As Berkshire Hathaway's CEO and chairman, Buffett recommends to his board of directors how much he should be paid, and decides the rest of the executives' compensation. The 90-year-old has received $100,000 a year since 1980 — a fraction of the $15 million average pay of S&P 500 CEOs in 2019.

Buffett doesn't earn much from other sources either. He netted double his salary in annual directors' fees in the 1990s and early 2000s, before he resigned as a director of The Washington Post Company and stepped down from other corporate boards.

The highest total compensation he's ever received at Berkshire was $525,000 in 2010, comprising his $100,000 salary, $75,000 in directors' fees, and $350,000 allocated to his security costs.

Berkshire spends far more on Buffett's personal and home security than it pays him directly. Keeping the boss safe has cost the company an average of $339,000 a year since 2008, or $4.4 million in total.

Buffett isn't in desperate need of a big salary. He owns roughly $100 billion of Berkshire stock — which he's gradually giving away — and doesn't spend much: he lives in a modest family home, drives a basic car, and eats breakfast at McDonald's.

The investor also doesn't use a company car, belong to any clubs where Berkshire pays his dues, or commandeer company-owned aircraft for his personal use.

Buffett shared his views on salaries at Berkshire's annual shareholder meeting in 2017, when he was asked how much his successor would be paid. He expressed hope that the next CEO would already be rich, and wouldn't be motivated to earn 10 or 100 times the money their family needs to live on.

"They might even wish to, perhaps, set an example by engaging for something far lower than, actually, what you can say their true market value is," he continued, adding it would be "terrific" if that was the case.

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Buffett is a firm believer that CEOs should be incentivized to deliver long-term success for their companies. He believes massive annual salaries, bonuses, and short-term stock options encourage short-term thinking.

Charlie Munger — Buffett's right-hand-man and Berkshire's vice-chairman — has followed Buffett's example. He's also received a salary of $100,000 a year for several decades now, SEC filings show.

In contrast, Ajit Jain and Greg Abel, who head up Berkshire's insurance and non-insurance divisions respectively, are paid far more handsomely. Both men have earned a $16 million salary in each of the past of three years, plus total bonuses of $7 million each.

Finally, Berkshire's finance chief, Marc Hamburg, has seen his salary grow from about $300,000 in 1996 to $3.3 million last year.