Reddit Joins S&P 500—Stock Skyrockets
Reddit Joins the S&P 500: What It Means for the Social Media Giant

Reddit mascot rings the opening bell at the New York Stock Exchange (NYSE) in New York City, March 21, 2024. Photo: Brendan McDermid | Reuters
What Just Happened?
Reddit is officially moving up to the big leagues. On Thursday, the social media company’s stock jumped 11% in after-hours trading after S&P Dow Jones Indices announced it will be added to the S&P 500 index on August 18.
Important Point: This is a major milestone for Reddit — it’s like getting promoted from the minor leagues to the majors in professional sports.
What Is the S&P 500? (ELI5 Explanation)
Think of the S&P 500 as a "greatest hits" playlist of America’s 500 largest public companies.
- It tracks how the biggest U.S. stocks are doing as a group
- When people say "the market is up," they often mean the S&P 500
- Index funds (popular retirement investments) automatically buy all 500 stocks in this list
Why does inclusion matter?
When a company joins the S&P 500, all those index funds must buy its shares to stay accurate. That forced buying often pushes the stock price up — exactly what happened with Reddit.
Reddit’s New Status: Rare Company in Elite Club
Reddit becomes only the second "pureplay" social media company in the S&P 500:
| Company | Status |
|---|---|
| Meta (Facebook/Instagram) | Already in S&P 500 — one of world’s most valuable companies |
| NEW — joining August 18 | |
| Public longer, but too small by market value | |
| Snap (Snapchat) | Public longer, but too small by market value |
| X (formerly Twitter) | Was in S&P 500 until Elon Musk bought it in 2022 — now private, owned by SpaceX |
Key Takeaway: Being a "pureplay" social media company means Reddit’s main business is social media — unlike Google or Apple, which have social features but make money other ways.
The Rollercoaster Ride: Reddit’s Recent Months
The Good News (July Earnings)
- 8th straight quarter of revenue growth over 60%
- Strong advertising sales
- Growing user base
The Scare (Stock Drop After Earnings)
Reddit warned investors: "Search referrals were choppy."
Translation: Fewer new users coming from Google searches.
The Culprit: Google’s AI Overviews
CEO Steve Huffman explained: Google’s new AI Overviews (powered by Gemini) now answer questions directly in search results — so people don’t need to click through to Reddit as often.
Simple Analogy: Imagine you ask a librarian a question. Before, they’d hand you a book (Reddit thread). Now, they just tell you the answer themselves (AI Overview). You never open the book.
Other Changes in the S&P Family
| Index | Change | Effective Date |
|---|---|---|
| S&P 500 | Reddit replaces AvalonBay Communities | August 18 |
| S&P MidCap 400 | Sun Communities replaces Webster Financial | August 18 |
Why This Matters for Regular Investors
Potential Benefits for Reddit
- More stable shareholder base — index funds hold long-term
- Increased visibility — more analysts cover S&P 500 stocks
- Prestige factor — signals maturity to advertisers and partners
Things to Watch
- Google dependence — can Reddit grow without search traffic?
- AI disruption — will AI answers keep replacing forum visits?
- Profitability pressure — S&P 500 companies face higher expectations
Summary
- Reddit joins S&P 500 on August 18, replacing AvalonBay Communities
- Stock surged 11% on the news — index funds must buy shares
- Only second pureplay social media company in the index (with Meta)
- Comes after strong earnings but warning about Google search traffic
- Google’s AI Overviews are sending fewer users to Reddit
- Sun Communities also moving up to S&P MidCap 400
Bottom Line: This is a vote of confidence in Reddit’s business model — but the company still needs to prove it can thrive in an AI-powered search world.
FAQ
1. What does "pureplay social media company" mean?
It means social media is the company’s main and essentially only business. Meta (Facebook, Instagram, WhatsApp) is the other example. Companies like Google or Apple have social features but make most money elsewhere.
2. Why did Reddit stock jump 11% just on this announcement?
Because index funds tracking the S&P 500 (trillions of dollars) must buy Reddit shares before August 18 to match the index. That guaranteed demand drives up the price.
3. What are "AI Overviews" and why do they hurt Reddit?
When you search Google now, you often see an AI-generated answer at the top — pulled from sites like Reddit. You get your answer without clicking through. Fewer clicks = fewer new users = less ad revenue.
4. Is Reddit now a "safe" investment because it’s in the S&P 500?
Not necessarily. S&P 500 inclusion means size and stability standards were met, but stock prices still go up and down based on earnings, competition, and the economy. Always do your own research.
5. What happens to AvalonBay Communities (the company Reddit replaced)?
It moves to the S&P MidCap 400 (mid-sized companies index). It’s not "kicked out" — just reclassified by size. Index changes happen quarterly as companies grow or shrink.
Want to watch the full story? CNBC Video: Reddit joining S&P 500 on August 18