3 reasons the S&P 500 will soar 14% through 2025, BMO says

• The S&P 500 will hit 6,700 next year, BMO's chief investment strategist has said.
• That's because the stock market is entering the third year of a cyclical bull run, Brian Belski said.
• He also said he saw strong earnings growth and lower interest rates boosting the market.

Don't bet on an S&P 500 stumble next year, as BMO Capital Markets sees more upside to come.

The benchmark index is headed for a 6,700 level by the end of 2025, BMO's chief investment strategist, Brian Belski, has said. That marks a nearly 14% increase from current levels.

There are three reasons to anticipate this outcome, he told CNBC on Monday.

First, the stock market is entering its third year of a cyclical bull rally. Since 1950, a cyclical bull year typically equates to a 6% gain for the index, Belski said.

Across the current bull cycle, the stock market has scored significantly larger annual gains than history would suggest. The S&P returned 24% in 2023 and is already up about 23% year to date.

Second, Belski said the index would notch more than just a 6% appreciation as earnings growth is understated.

There's some anxiety that the stock market has become too expensive, with valuations hovering at near generational highs. BlackRock's bond chief, Rick Rieder, recently said earnings growth would need to rise significantly for stock-market multiples to come down.

Belski said this would happen and predicted that the market would continue broadening out away from a heavy focus on a few leading names. This has been a concern, given that just a handful of tech names account for roughly a third of the S&P.

"We see the broadening-out effect to be real," Belski said, later adding: "You take a look at the other 490 stocks in the S&P 500, their earnings growth is expanding a lot faster."

Third, markets will continue responding to easing monetary policy.

"If you look at monetary policy and fiscal policy, that's what really drives markets, and the train has left the station with respect to monetary policy becoming more loose," he said.

The Federal Reserve has so far cut interest rates twice since September, and investors indicate a 65.3% chance of another quarter-point cut in December, CME FedWatch data shows.

Though the market is less sure on how far interest rates can fall under president-elect Donald Trump's policies, Goldman Sachs has predicted that the federal funds rate drop more than 100 basis points to a 3.25% to 3.5% range next year.

BMO's prediction is a rung above other forecasts. On Monday, Morgan Stanley updated its 2025 S&P target to 6,500, saying high-quality cyclical stocks would outperform.