S&P 600 Index Addition: Stock Price Increase on addition to S&P 600
Addition of a stock to S&P 600 Index leads to an increase in the price of the stock - sometimes by upto 15% within a day. During Sept-2018 to Aug-2025, about 222 stocks were added to the S&P 600 index as a new addition. In this research, we provide the potential return from buying stocks added to S&P indexes and how to use our Alerts ( or Notifications) on Phone & email to learn about these additions before others & make these trading decisions.
Company Name | Ticker | Announced Date | Effective Date | Source Index | % Change by Next Day Close |
|---|---|---|---|---|---|
Champion Homes | SKY | 12/06/2024 | 12/23/2024 | None | 10.17590316 |
International Seaways | INSW | 12/23/2024 | 12/30/2024 | None | 9.427904262 |
Grid Dynamics Holdings | GDYN | 12/26/2024 | 01/02/2025 | None | 12.63403263 |
Acadia Pharmaceuticals | ACAD | 12/30/2024 | 01/03/2025 | None | 7.826834862 |
Acushnet Holdings | GOLF | 02/10/2025 | 02/13/2025 | None | 11.87644788 |
Kadant | KAI | 02/13/2025 | 02/19/2025 | None | 12.63542946 |
SanDisk | SNDK | 02/19/2025 | 02/25/2025 | None | 0 |
Ryman Hospitality Properties | RHP | 03/07/2025 | 03/24/2025 | None | 3.094738944 |
Element Solutions | ESI | 03/07/2025 | 03/24/2025 | None | 4.994054697 |
WillScot Holdings | WSC | 03/07/2025 | 03/24/2025 | None | 6.201550388 |
Freshpet | FRPT | 03/07/2025 | 03/24/2025 | None | 7.185019336 |
Mueller Water Products | MWA | 03/07/2025 | 03/24/2025 | None | 8.179315769 |
CleanSpark | CLSK | 03/07/2025 | 03/24/2025 | None | 9.873708381 |
Kratos Defense & Security Solutions | KTOS | 03/07/2025 | 03/24/2025 | None | 10.74829731 |
ANGI | ANGI | 03/26/2025 | 04/02/2025 | None | 7.121303561 |
Enact Holdings | ACT | 04/09/2025 | 04/16/2025 | None | 4.588471465 |
Sterling Infrastructure | STRL | 04/14/2025 | 04/17/2025 | None | 9.898215076 |
Victory Capital Holdings | VCTR | 07/15/2025 | 07/18/2025 | None | 6.670673077 |
Veracyte | VCYT | 07/24/2025 | 07/29/2025 | None | 8.340248963 |
Kodiak Gas Services | KGS | 08/01/2025 | 08/06/2025 | None | 0.330628194 |
% Change by Next Day Close = % Change [ Maximum of [High Price between Announce Date_17:15 hrs EST & Announce Date+1_19:59 hrs EST] / Minimum of [Low Price on Announce Date betw 17:15 & 17:20 hrs EST] ]
01
Average 6.4% Return from Stocks Added to S&P500 between 2018-Sept to 2025-Aug
An average 6.4% price swing per stock in just over a day — compounded across 96 additions to the S&P 500 between September 2018 and August 2025 — translates into a jaw-dropping 612% cumulative return. To put that in perspective, the S&P 500 index itself returned only about 150% over the same period, and even Warren Buffett’s Berkshire Hathaway — the gold standard of long-term investing — delivered far less. Achieving 612% in seven years isn’t just beating the market; it’s multiplying it several times over. In a world where fund managers celebrate a few percentage points of annual “alpha,” these index-inclusion surges reveal a rare, structural opportunity that has outperformed virtually every conventional benchmark by a wide margin.
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Based on analysis of 96 stocks that were added to S&P500 Index between September-2018 and August-2025, we found that the these stocks underwent a price change of 6.4% - from the “minimum price during the first five minutes after announcement of addition to index” to the “maximum price reached by the end of next trading day(after hours trading)”. The total return from this price swing of these 96 stocks was 612%.
02
Return from Stocks Added to S&P500:2021Dec to 2024-Sept
Our research indicates - buying a stock that gets added to S&P500 Index, within a few minutes of the announcement and selling it by market-open on next day has returned about 3% for the investors, during the period from 2021 December to 2024 September.
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An analysis of 40 stocks added to S&P500 Index during the period between 2021-December to 2024-September shows the following: Buying these stocks within about 5 minutes of the announcement of addition and selling by next-day open of markets provided a return of about 3% per stock.
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The table here shows the return from "Closing Price" on Announcement-Day to "Open Price" on "Next Day".
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