Reddit Inc. (NYSE: RDDT) will join the S&P 500 before the market opens on August 18, 2026, following an announcement by S&P Dow Jones Indices on August 13. Shares jumped 11% in after-hours trading on the news.

Reddit will replace AvalonBay Communities Inc. in the S&P 500. AvalonBay’s removal follows its agreement to be acquired by Equity Residential, creating the vacancy for Reddit’s addition. The change is an off-cycle constituent swap, ending months of speculation about Reddit’s entry into the benchmark index.

Shares rose sharply in extended trading after the announcement, with coverage concentrated in the hour following the market close. The off-cycle inclusion is expected to boost passive index demand for Reddit shares ahead of the effective date, generating a narrow window for reconstitution-driven buying from index-tracking funds.

Shares of Reddit (NYSE:RDDT | RDDT Price Prediction) are rallying Friday afternoon after S&P Dow Jones Indices announced late Thursday that the stock will be added to the S&P 500 prior to the start of trading on Tuesday, Aug.

Reddit Is Still Down 24% This Year. What Will It Take to Get RDDT Stock Back Up to $200?

S&P 500 pulls back from a record as tech selling, weak consumer data and rising oil outweigh Reddit's index-inclusion rally.

S&P500: Reddit's Inclusion Bid Fails to Lift Weakening Stock Market Sentiment

Reddit stock surged 11% after the company was announced as a new addition to the S&P 500, replacing AvalonBay Communities on Aug. 18. JPMorgan estimates index funds will need to purchase approximately 16.7 million Reddit shares to match the index's weighting.

Why Reddit Stock Just Gained 10.7%

Shares in Reddit, Inc. (NYSE: RDDT) are surging in premarket trading this morning after S&P Dow Jones Indices announced that the social media platform will join its prestigious S&P 500 Index.

Reddit is joining the S&P 500. Here's why that matters, and why the stock price is surging on the news

As of 11:39 AM ET, the S&P 500 (^GSPC -0.15%) has fallen 0.21% to 7,782.65, and the Nasdaq Composite (^IXIC -0.42%) is down 0.50% to 26,664.30 as investors balance recent record highs against soft retail data. The Dow Jones Industrial Average (^DJI -0.18%) has slipped 0.19% to 53,735.56.

Stock Market Midday, Aug. 14: Stocks Wobble on Falling Consumer Confidence, Reddit Jumps 14%

Index additions have become one of the most reliable short-term catalysts in the stock market.

Reddit Is Getting Added to the S&P 500 — But You Still Shouldn't Buy It

Reddit Inc (NYSE:RDDT) shares jumped more than 16% on Friday after S&P Dow Jones Indices said the company will join the S&P 500 index next week. The inclusion is expected to trigger mandatory buying from institutional funds that track the benchmark.

Reddit stock soars after S&P 500 inclusion announcement

Tesla shares surged 60% between the announcement of its S&P 500 inclusion and its addition to the index in December 2020, marking one of the largest inclusion-driven rallies on record, according to Charles Schwab. Other stocks don't hold onto an index-driven bump, however: Workday, which jumped nearly 10% on news of its inclusion, dropped 19% from its peak after joining the index in December 2024.

Reddit Joins The S&P 500 Next Week—Here's What That Means For Shares

Reddit stock is getting a much-needed boost on its admission into a major index.

Social Media Giant Reddit Is Set to Join the S&P 500 Soon. Its Stock Is Soaring

Shares in Reddit Inc (NYSE:RDDT), the social media platform, surged 12.45% in extended trading on Thursday after S&P Dow Jones Indices announced the business will join the S&P 500. The company will enter the prominent equity index before the US market opens on August 18.

Reddit set for indexation boost, due on S&P 500 later this month

Shares of Reddit Inc (NYSE:RDDT) are up 11.5% at $176.25 before the open, after news that the social media platform will join the S&P 500 Index (SPX) on Aug. 18, replacing AvalonBay Communities (AVB).

Reddit Stock Jumps on S&P 500 Inclusion

Although Wall Street loves a clean catalyst, and index inclusion is about as clean as they come, the record of the past year suggests the party rarely lasts.

Reddit is Up 11% Premarket After S&P 500 Addition. Here's How Other New S&P 500 Stocks Performed.

SAN FRANCISCO--(BUSINESS WIRE)--Reddit, Inc. (NYSE: RDDT) will join the S&P 500 index, effective prior to market open on Tuesday, August 18th. Its addition to the S&P 500 underscores Reddit's value, sustained performance as a public company, and its 1-of-1 financial model, highlighted by a rare combination of growth and best-in-class profit and cash flow margins. “We're proud to be added to the S&P 500, recognizing the growth, momentum, and consistency we've established as a public.

Reddit Will Be Added to the S&P 500

Reddit (RDDT) will join the S&P 500, replacing AvalonBay Communities, driving RDDT shares up ~12% pre-market. Applied Materials (AMAT) delivered strong Q3 results and guidance, but shares fell 5% as investors expected more after a 98% YTD run.

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Reddit rallies with the social-media platform set to join the S&P 500, while Applied Materials dips after earnings fail to wow investors.

Sandisk, Reddit, Applied Materials, and More Stocks That Explain Today's Market

Reddit shares jumped more than 11% on Friday after the S&P Dow Jones Indices said the ​social media platform would join the benchmark S&P 500 ‌index, replacing AvalonBay Communities.

Reddit surges on S&P 500 inclusion, set to replace AvalonBay

Mid-August 2026 might prove to be one of the best buying opportunities ever presented to hopeful Reddit (NASDAQ: RDDT) stock investors.

Why you should buy Reddit stock before August 18

Reddit shares climbed nearly 13% in extended trading on Friday after S&P Dow Jones Indices announced that the social media platform will join the S&P 500, marking a significant milestone for the company less than two years after its public listing. The company will enter the benchmark index on Aug. 18, replacing AvalonBay Communities.

Reddit stock surges on S&P 500 inclusion, but Google search referral woes remain

After past snubs, social-media site Reddit has landed a spot on the S&P 500, sending shares on an after-hours rally Thursday.

Reddit is joining the S&P 500 after months of speculation. Analysts have these concerns.

After getting passed over multiple times this year, Reddit Inc. (NYSE:RDDT) is finally punching its ticket into the S&P 500.

Reddit Stock Pops on Long-Awaited S&P 500 Inclusion

NEW YORK, Aug. 13, 2026 /PRNewswire/ -- S&P Dow Jones Indices will make the following changes to the S&P 500 and S&P MidCap 400:  Reddit Inc. (NYSE: RDDT) will replace AvalonBay Communities Inc. (NYSE: AVB) in the S&P 500 effective prior to the opening of trading on Tuesday, August 18. S&P 500 constituent Equity Residential (NYSE: EQR) is acquiring AvalonBay Communities in a deal expected to be completed soon, pending final conditions.

Reddit Set to Join S&P 500 and Sun Communities to Join S&P MidCap 400

The social media platform will replace AvalonBay Communities before the market opens on Tuesday.

Reddit Will Join the S&P 500. The Stock Jumps 11%.

Reddit stock jumped late Thursday on news that the social media firm will join the S&P 500 index. Sun Communities will be added to the S&P MidCap 400.

Reddit Stock Jumps On S&P 500 News

Reddit shares 11% in extended trading on Thursday on the social media company's inclusion in the S&P 500. The social media company will join the S&P 500 on Aug 18, replacing AvalonBay Communities Inc.

Reddit shares jump 11% on inclusion in S&P 500

Reddit surged after hours after being added to the S&P 500, replacing AvalonBay Communities on Aug. 18. The inclusion marks a major milestone for the social media company and boosted investor sentiment.

Reddit S&P 500 inclusion lifted shares in after-hours trading and could spur passive index demand ahead of the Aug. 18, 2026 effective date.

Reddit S&P 500 Inclusion Sends Shares Higher

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Reddit S&P 500 Inclusion Sends Shares Higher

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