The criteria are you have to qualify for several months or quarters or something

To qualify for inclusion in the S&P 500, a company has to meet strict criteria set by S&P Dow Jones Indices. It’s not just the biggest companies by market cap — the committee looks at financial health, structure, and liquidity too. Here are the main requirements:

Eligibility Criteria

Domicile: Must be a U.S. company (incorporated and headquartered in the U.S.).

Exchange: Must trade on the NYSE (including NYSE Arca), NASDAQ, or Cboe.

Market Cap: At least about $18 billion (reviewed and adjusted over time).

Liquidity:

Annual dollar value traded / float-adjusted market cap ratio ≥ 1.0.

Minimum monthly trading volume of 250,000 shares in each of the six months before evaluation.

Public Float: At least 50% of shares outstanding must be available to the public (not held by insiders).

Financial Viability: Positive earnings in the most recent quarter and in aggregate over the last four quarters.

Sector Representation: The committee also considers whether the company helps maintain balance across industries.

Exclusions

Closed-end funds, ETFs, royalty trusts, limited partnerships, OTC stocks, and preferred shares are not eligible.

Important nuance:

Even if a company meets all the criteria, the S&P Index Committee has discretion. They sometimes delay or deny inclusion if the company’s business model, governance, or sector weight raises concerns (e.g., Tesla was eligible for years before inclusion in 2020).

---

Want me to give you some examples of firms that qualified recently and why they got in? That might show how the committee applies these rules in practice.