Are U.S. Stocks Overvalued? Everyday Investors and Experts Disagree

As the stock market continues to set record highs, an increasing number of investors are concerned with skyrocketing valuations. But are stocks too expensive today? And if so, is the market in a bubble that's due to pop? The answers depend on who you ask.

The broad-based S&P 500 has climbed by roughly 15% in the past year alone, and the index's total value has more than doubled from its pre-pandemic norms. (Exactly six years ago, the S&P 500 closed at 2,926.46. Yesterday, it closed at 6,411.53.)

The index's price-to-earnings (P/E) ratio — a metric that represents investors' expectations for a company's future growth, and how much of a premium they're willing to pay for every dollar a company earns — is a historically high 29.85, compared to a median of 17.97.

All of this would suggest an overabundance of optimism on the part of investors. A recent Bank of America survey found that a record-high 91% of respondents think stocks today are overvalued, the highest figure since the bank began the survey in 2001. According to Vanguard, U.S. stocks today are overvalued by nearly 50%.

Investors are enthusiastic despite lofty valuations

There is evidence that the market's current buoyancy owes a great deal to retail investors' zeal. Call it the FOMO effect: As valuations rise, more people want in — especially retail investors. Data from Gallup shows that the number of Americans who own stock has jumped by 10 percentage points over the past decade.

"What I see in the stock market is rising demand for stocks. People want to get in, people want to stay in," says Michael Kahn, senior vice president and senior market analyst at the Lowry Research division of CFRA Research. "The desire to sell has been diminished."

Those investors might share the same sentiment as numerous market pros, who say there are other signals that suggest most — if not all — of the current market growth is grounded in fundamentals rather than fantasy.

"Valuations are certainly elevated. The question is, should they be?" says Mike Dickson, head of research at Horizon Investments. "We just came off of earnings season and, given what we've just seen, valuations seem appropriate."

AI is the 'tip of the spear' driving market growth

There's one reason why investing pros remain optimistic about future earnings: AI.

"AI is the tip of the spear as it relates to technology in this day and age," Dickson says. Big tech companies are pouring money into AI investments as they chase the promise of huge gains in productivity and, ultimately, earnings. If they succeed, rather than being overvalued, Dickson says that it's very possible the market is underpricing the productivity possibilities with AI.

Comparisons to the frothy, tech-fueled investor enthusiasm in the late 1990s that immediately preceded dot-com crash of 2000 are perhaps inevitable, but there are some key differences that should assuage investors' worries.

"The companies leading the top of the market today are extremely high-quality, massive market firms," Dickson says. "When you look back to the '90s … it was more speculative."

That said, while many experts are similarly upbeat about the technology's potential, they acknowledge that there are a lot of forward-looking assumptions baked into current valuations that might not pan out like investors are hoping.

What and where are the risks?

This is all a game of expectations, according to Jeff Buchbinder, chief equity strategist at LPL Financial. "Right now, valuations reflect a lot of optimism about profit growth in the coming years," he says. "They're probably also reflecting anticipated future Fed rate cuts and a lower 10-year [Treasury note] yield."

If inflation — and interest rates — remain elevated, those expectations could be harder to achieve. In addition, there's one big caveat with all of the AI enthusiasm: In many cases, performance hasn't (yet) lived up to the hype.

"The promise of a lot of the productivity gains from AI have largely not found their way into the economy yet, so that becomes a 2026 story," says Eric Teal, chief investment officer for Comerica Wealth Management. "We have to see the productivity gains, the sales growth. A lot of the promise that AI promotes needs to bear fruit."

If this promise isn't kept, high-flying tech stocks — and the indices affected by their enormous weightings — could be at risk. "If AI gains do not bear themselves out and trickle down, then the degree of concentration in the market is excessively high, which would be concerning for a market correction," Teal cautions.

Teal and others raise concerns about concentration risk. The top 10 stocks in the S&P currently contribute nearly 40% of the overall market’s value. "[This] is very concerning from a diversification standpoint," he says.

In particular, the so-called Magnificent Seven stocks are where the most extreme growth — and the highest investor expectations — are centered. Calculating the P/E ratio for these seven companies using estimated earnings for the coming year as the denominator gets you a figure of roughly 30, Buchbinder says. For the other 493 companies in the S&P, that collective P/E ratio is 20. "It's simple numbers," he says, pointing out that under current market conditions, even a stumble from any of those firms would be a seismic event.

While excessive concentration is a concern, it's not the only potential stumbling block for the market. Worry about the persistence of inflation — and the higher borrowing costs associated with it — as well as the impact of tariffs on companies' costs and profits have the potential to chill investor enthusiasm.

"Tariffs, in particular, remain a wild card that could leave investors playing a much weaker hand than anticipated," Buchbinder says. "The stock market is pricing in near-clarity [with tariffs], and we probably need a little bit of a nod to the fog that still needs to clear … because the inflationary effects are just starting to be felt."

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