S&P 500 Q1 2026 Additions: 4 New Stocks Confirmed with 100% Market Probability

Half a billion dollars in market volume says these four stocks are joining the S&P 500 in Q1 2026. Vertiv Holdings, Lumentum Holdings, Coherent, and EchoStar received the green light from S&P Dow Jones Indices — and the market prices them certainty at 100%.

Key Takeaways

Vertiv Holdings, Lumentum Holdings, Coherent, and EchoStar are the four confirmed additions to the S&P 500

Market prices in 100% probability with over 600K in trading volume

**Changes effective after market close on March 20, 2026

Replacements: Vertiv replaces Alexander & Baldwin, Lumentum replaces Univar, Coherent replaces International Flavors & Fragrances, EchoStar replaces Sealed Air

Current Market State

The S&P 500 is getting four new members in Q1 2026, and the market is absolutely certain about it. According to Polymarket, $607,204 in trading volume backs a 100% probability that Vertiv Holdings, Lumentum Holdings, Coherent, and EchoStar will join the index.

This is not speculation — it is done. S&P Dow Jones Indices confirmed the changes on March 6, 2026. The additions will be effective after the close of trading on Friday, March 20, 2026.

What makes this different from typical index changes: These are not contested additions. They are confirmed, announced changes with clear replacement targets. The market sees no uncertainty.

Key Data

Indicator | Value | Signal
Trading Volume | $607,204 | High conviction
Current Probability | 100% | Certainty
Effective Date | March 20, 2026 | Imminent
Companies Added | 4 | Diversification

Analysis

Since S&P Dow Jones Indices already announced these changes officially, the 100% probability reflects market confidence in the execution. This is a rare case where prediction markets align with corporate announcements rather than speculation.

The Four New Additions:

Vertiv Holdings (VRT) - Replaces Alexander & Baldwin (ALE)

Lumentum Holdings (LITE) - Replaces Univar (UNVR)

Coherent (COHR) - Replaces International Flavors & Fragrances (IFF)

EchoStar (SATS) - Replaces Sealed Air (SEE)

Each replacement follows S&P's methodology of swapping out smaller or less representative companies for those that better reflect the current market composition.

Settlement Criteria

This Polymarket market resolves based on the official S&P Dow Jones Indices announcement after market close on March 20, 2026.

The market resolves Yes if all four companies — Vertiv Holdings, Lumentum Holdings, Coherent, and EchoStar — are added to the S&P 500 as announced.

The market resolves No if any of the additions do not occur as planned.

What to Watch

March 20, 2026 (Market Close): The effective date of the additions. Watch for any last-minute changes or announcements from S&P Dow Jones Indices.

Index fund flows: On March 20, billions in passive fund flows will need to acquire positions in all four stocks.

Pre-addition volume: Increased institutional buying ahead of the formal inclusion could drive share prices higher.

FAQ

Which companies are being added to the S&P 500 in Q1 2026?

Vertiv Holdings (VRT), Lumentum Holdings (LITE), Coherent (COHR), and EchoStar (SAT) are the four confirmed additions. These stocks will replace Alexander & Baldwin, Univar, International Flavors & Fragrances, and Sealed Air respectively.

When do the S&P 500 changes take effect?

The changes will be effective after the close of trading on Friday, March 20, 2026. This gives index funds and institutional investors two weeks to prepare for the rebalancing.

How does this affect S&P 500 index funds?

Passive index funds tracking the S&P 500 will automatically adjust their holdings on March 20. This typically triggers billions in fund flows as funds acquire positions in the newly added stocks while divesting from the removed companies.

Prediction

Direction: Neutral | Probability: 100% | Horizon: 13 days
Answer: Yes

This is a confirmed event with an official announcement from S&P Dow Jones Indices. The market reflects 100% probability with high trading volume, making this a near-certainty outcome.

How to Trade This

This prediction trades on Polymarket. Buy Yes shares at 99c (99% implied probability) if you agree, or No at 1c if you expect a last-minute change. Each share pays $1 if correct, $0 if wrong. Sell anytime before resolution.