The S&P 500 jumped in September, stringing together the fifth-straight monthly gain. And some stocks scored seriously impressive gains.
If you invested $10,000 in January in the top-performing stock in the S&P 500 at the time and reinvested that in each month's top performer, including Warner Bros. Discovery in September, you'd have $187,543 now, says an Investor's Business Daily analysis of data from S&P Global Market Intelligence and MarketSurge.
That's an impressive seven-month gain of 1,775%. It's quite a feat given the S&P itself is up just 13.7% so far this year. It's the best one-month stock gain of any S&P 500 stock this year. And the same $10,000 invested in the S&P 500 would be worth just $11,370 now. That's a gain of $1,370. The S&P 500 rose 3.5% in September, making it the sixth positive month this year since January.
Will The S&P 500 Sink In October?
Hindsight is 20-20. And, clearly, few if any investors could have picked the top stock in each of the past nine months, as it's not a repeatable strategy. But the staggering numbers this year remind investors that amazing gains can be scooped up by diligent investors who keep buy lists handy for big leaders when the S&P 500 starts to hit highs.
In fact, in the five-straight months of gains, the S&P 500 offered many ways to make money. Nearly half the stocks in the S&P 500 rose during September. And of those, 14 stocks jumped more than 20% in just one month.
Top S&P 500 Stock Of September: Warner Bros. Discovery
The S&P 500 itself was so strong in September that competition to be No. 1 was fierce. Warner Bros. Discovery was well positioned. The company is in play for a buyout following the merger creating entertainment giant Paramount Skydance. Warner Bros. Discovery rose 67.8% this month, marking the best monthly performance of any S&P 500 stock this year so far.
It marked the first month this year with a communications stock on top of the S&P 500. Last month, additives and chemicals maker Albemarle was the top stock with a 25.2% rally.
Analysts think that Warner Bros.' earnings per share will rise 108% in 2025. And profit is seen sinking 184% in 2026. This is not the time to buy the stock, though. The RS Rating is 96 and EPS Rating is 68, out of 99. But the stock is also well extended past its 200-day moving average.
The rest of the top 10 S&P 500 stocks in the ninth month of the year include a mixed bag of equities. Mobile apps platform AppLovin shares gained 50% in September, putting them up 122% for the year. Digital storage firm Western Digital is also continuing to bounce. Shares of the AI storage player rose even more than 49% in September.
What's Coming Next For The S&P 500?
The big question, though, is: Will the S&P 500's winning ways continue in October? Historically, the odds are poor. October is a month known for scary crashes.
October ranks seventh of all 12 months for S&P 500 performance going back to 1950, says the "Stock Trader's Almanac." The S&P 500 gains just 0.8% in September on average. Investors also have the risk of tariffs along with layoffs to contend with.
Following fives solid months for the S&P 500, investors hope for more gains. But it's unclear if they'll get more.
How To Turn $10,000 Into $187,543 In 9 Months
| Month | Top S&P 500 stock | Symbol | Monthly gain | Sector | S&P 500 monthly ch. | Starting balance | Cumulative value of $10,000 investment in January reinvested in best stock each month |
|---|---|---|---|---|---|---|---|
| January | Constellation Energy | CEG | 34.1% | Utilities | 2.7% | $10,000 | $13,410 |
| February | Super Micro Computer | SMCI | 45.4% | Information Technology | -1.4% | $13,410 | $19,498 |
| March | Dollar General | DG | 18.5% | Consumer Staples | -5.8% | $19,498 | $23,105 |
| April | Palantir Technologies | PLTR | 40.3% | Information Technology | -0.8% | $23,105 | $32,417 |
| May | NRG Energy | NRG | 42.3% | Utilities | 6.2% | $32,417 | $46,129 |
| June | Coinbase Global | COIN | 42.4% | Financials | 5.0% | $46,129 | $65,688 |
| July | Generac Holdings | GNRC | 35.9% | Industrials | 2.2% | $65,688 | $89,270 |
| August | Albemarle | ALB | 25.2% | Communication Services | 1.9% | $89,270 | $111,766 |
| September | Warner Bros. Discovery | WBD | 67.8% | Communication Services | 3.5% | $111,766 | $187,543 |
