The United States has 29 national securities exchanges registered with the Securities and Exchange Commission, more than any other country. The New York Stock Exchange and the Nasdaq Stock Market handle most equity trading volume, but the full set of US stock exchanges includes venues run by Cboe, MIAX, and several independents, alongside off-exchange trading systems and over-the-counter markets for securities that don’t qualify for a major listing. Every exchange must register under the Securities Exchange Act of 1934, enforce its own rules against fraud and manipulation, and submit to ongoing federal oversight.1Office of the Law Revision Counsel. 15 USC 78f – National Securities Exchanges
The New York Stock Exchange
The NYSE is the world’s largest stock exchange by market capitalization of listed companies. It uses an auction market model, meaning buyers and sellers interact directly to set prices rather than routing through an intermediary dealer. The key figures on the NYSE floor are Designated Market Makers, or DMMs. Each listed stock is assigned to a DMM firm that commits its own capital to keep trading orderly. When there aren’t enough buyers, the DMM steps in and buys; when sellers disappear, the DMM sells from its own inventory.2NYSE. Designated Market Makers – Improving Liquidity and Market Quality
DMMs are held to stricter obligations than ordinary market makers. They must quote competitive prices at multiple levels of the order book, not just at the best bid and offer. They also play a critical role at the open and close of each trading day, when volume spikes and volatility tends to be highest. At those moments, DMMs contribute capital and use human judgment to set prices that reflect true supply and demand.3NYSE. NYSE Paper on Market Making
The NYSE’s core equity session runs from 9:30 a.m. to 4:00 p.m. Eastern Time, Monday through Friday, and the exchange closes on federal holidays including New Year’s Day, Martin Luther King Jr. Day, Presidents’ Day, Good Friday, Memorial Day, Juneteenth, Independence Day, Labor Day, Thanksgiving, and Christmas.4NYSE. Holidays and Trading Hours
The Nasdaq Stock Market
Nasdaq launched in 1971 as the first electronic quotation system and became a fully registered national securities exchange in 2006. Unlike the NYSE’s auction model, Nasdaq operates as a dealer market where multiple competing market makers post bid and ask prices for each stock. Trades execute through an electronic matching engine rather than on a physical floor, which suits high-frequency, automated trading.
Nasdaq splits its listings into three tiers with progressively higher requirements. The Nasdaq Global Select Market sits at the top and demands the most from applicants: at least $45 million in publicly held shares, 450 or more round lot shareholders, and financial benchmarks that can include $11 million in aggregate pretax earnings over three years. The Nasdaq Global Market occupies the middle tier. The Nasdaq Capital Market is the entry-level tier, requiring a minimum bid price of $4 per share, at least 300 round lot holders, and either a market value of listed securities of at least $50 million or net income of $750,000 or more.5The Nasdaq Stock Market. Nasdaq Code 5500 – The Nasdaq Capital Market
The Other 27 Registered Exchanges
Beyond the NYSE and Nasdaq, the SEC’s roster of registered exchanges includes 27 other venues. Most are operated by a handful of parent companies and serve specialized purposes.6U.S. Securities and Exchange Commission. National Securities Exchanges
The NYSE family includes NYSE Arca (primarily ETFs), NYSE American (small-cap equities, formerly the American Stock Exchange), NYSE National, and NYSE Texas (formerly the Chicago Stock Exchange). Each operates under the NYSE umbrella with different fee structures and order types.
The Nasdaq family adds Nasdaq PHLX (one of the oldest options exchanges, formerly the Philadelphia Stock Exchange), Nasdaq ISE, Nasdaq GEMX, Nasdaq MRX, and Nasdaq Texas, handling options and equities across multiple venues.
The Cboe family runs Cboe Exchange, one of the largest options markets in the world, along with Cboe BZX, Cboe BYX, Cboe EDGA, Cboe EDGX, and Cboe C2. These offer different combinations of equity and options trading, with pricing models designed to attract different types of order flow.
The MIAX family — Miami International Securities Exchange, MIAX Emerald, MIAX PEARL, and MIAX Sapphire — focuses on options trading.
Several independents fill out the list. Investors Exchange (IEX) gained attention for an intentional 350-microsecond speed bump that reduces advantages for high-frequency traders. The Long-Term Stock Exchange emphasizes governance standards for companies focused on long-term value. MEMX was founded by a consortium of brokerages and market makers to reduce trading costs. Newer entrants include Texas Stock Exchange, 24X National Exchange, and Green Impact Exchange.
The sheer number of exchanges can be confusing, but in practice most retail investors never choose which one handles their order. Your broker’s routing algorithm picks the venue offering the best available price at that moment, which is why competition among exchanges matters even if you never think about it.
Off-Exchange Trading: Dark Pools and OTC Markets
Not every US trade happens on a registered exchange. Two separate systems sit outside that group.
Alternative trading systems, often called dark pools, are private venues that match buy and sell orders without displaying quotes publicly before a trade executes. Large institutional investors use them to move big blocks of stock without tipping off the market and moving the price against themselves. These systems are not registered as exchanges. They register as broker-dealers and comply with Regulation ATS, which requires them to file detailed operational disclosures with the SEC, maintain daily trading records, and preserve those records for at least three years.7eCFR. 17 CFR Part 242 – Regulation ATS – Alternative Trading Systems Completed trades still get reported to the consolidated tape.
Over-the-counter markets serve companies that don’t qualify for an exchange listing: smaller, foreign, or financially distressed issuers. OTC Markets Group organizes them into three tiers. OTCQX is the top tier, requiring companies to meet financial standards and maintain at least 50 beneficial shareholders each holding 100 or more shares; the OTCQX Premier designation raises that minimum to 100 shareholders. OTCQB serves as the venture market for earlier-stage companies. OTC Pink has minimal requirements and includes highly speculative or delinquent issuers.8OTC Markets. OTCQX U.S. and OTCQB Disclosure Guidelines
Under SEC Rule 15c2-11, a broker-dealer cannot publish price quotes for an OTC security unless certain financial information about the issuer is publicly available, including a balance sheet dated within 16 months and recent profit-and-loss statements.
How the SEC Oversees Exchanges
Every national securities exchange operates as a self-regulatory organization, meaning it writes and enforces its own rulebook for member firms and listed companies. The SEC has ultimate authority over the entire system. Under Section 6 of the Securities Exchange Act, an exchange can only register if its rules are designed to prevent fraud, promote fair dealing, and avoid unfair discrimination among market participants.1Office of the Law Revision Counsel. 15 USC 78f – National Securities Exchanges
When an exchange wants to change its rules, whether adjusting fee schedules or modifying order types, it must file the proposed change with the SEC. The agency publishes the proposal for public comment before deciding whether to approve it. The SEC can also suspend or revoke an exchange’s registration for failing to enforce its own rules. Civil penalties for violations can reach $500,000 per act for an entity when fraud or reckless disregard is involved and causes substantial losses, and multiple violations can stack quickly.9Office of the Law Revision Counsel. 15 USC 78u-2 – Civil Remedies in Administrative Proceedings
Exchanges must also comply with Regulation Systems Compliance and Integrity, known as Reg SCI. This rule requires them to maintain written policies ensuring their trading systems have adequate capacity, security, and resilience. Penetration testing of networks and firewalls must happen at least every three years, and exchanges must conduct a full compliance review annually.10eCFR. 17 CFR Part 242 – Regulation SCI – Systems Compliance and Integrity
The SEC funds its operations partly through Section 31 transaction fees, which exchanges collect on sales of securities and remit to the agency. For fiscal year 2026, the rate is $20.60 per million dollars of securities sold. The fee is tiny on any individual trade but generates billions in aggregate across the market.11Federal Register. Order Making Fiscal Year 2026 Annual Adjustments to Transaction Fee Rates
Circuit Breakers and Trading Halts
Markets have built-in safety mechanisms to prevent panic-driven collapses. Market-wide circuit breakers trigger when the S&P 500 drops a certain percentage in a single day. A Level 1 decline of 7% halts trading for 15 minutes if it happens before 3:25 p.m. ET, with no halt if it hits after that. A Level 2 decline of 13% follows the same rule. A Level 3 decline of 20% halts trading for the rest of the day, whatever the time. Thresholds are recalculated daily based on the prior session’s closing price.12Investor.gov. Stock Market Circuit Breakers
Individual stocks have a separate protection called the Limit Up-Limit Down mechanism. Every stock gets a price band calculated from its recent trading price. For large-cap stocks above $3, the band is 5% in either direction. For smaller stocks, it widens to 10% or more. If a stock’s quoted price hits the edge of its band and doesn’t recover within 15 seconds, trading pauses for five minutes. In the final 25 minutes of the trading day, the bands double to accommodate the natural increase in closing volatility.13Limit Up-Limit Down. Limit Up Limit Down Plan
SIPC Protection for Brokerage Customers
If your brokerage firm fails financially, the Securities Investor Protection Corporation covers up to $500,000 in missing customer assets, including a $250,000 sublimit for cash. SIPC does not protect against investment losses or bad advice. It only kicks in when a broker-dealer goes under and customer accounts can’t be made whole. Unregistered digital asset securities are not covered.14SIPC. What SIPC Protects
Getting Listed and Staying Listed
Listing on a national exchange gives a company access to a broad pool of investors and the credibility that comes with meeting rigorous financial and governance standards. Specific requirements vary by exchange and tier, but the core categories are the same: financial minimums, shareholder distribution, and corporate governance.
The NYSE offers two main paths to initial listing. Under its earnings test, a company needs at least $40 million in market value of publicly held shares and a stock price of at least $4. Under the global market capitalization test, the bar rises to $200 million in total market cap. Both paths require at least 400 round lot holders and a minimum of 1.1 million publicly held shares.15NYSE. NYSE Initial Listing Standards Summary
Both the NYSE and Nasdaq require listed companies to have a board of directors where a majority of members are independent from management. Each company must maintain an audit committee made up entirely of independent directors who oversee financial reporting and internal controls. Executive compensation must be disclosed, and the company’s CEO must certify compliance with the exchange’s governance rules annually.16U.S. Securities and Exchange Commission. NASD and NYSE Rulemaking – Relating to Corporate Governance
Once listed, companies must keep filing annual reports on Form 10-K and quarterly reports on Form 10-Q with the SEC. The most common trigger for delisting is a stock price that falls below the exchange’s minimum. On Nasdaq, if a company’s bid price drops below $1.00 for 30 consecutive business days, the exchange sends a deficiency notice. The company then gets 180 days to bring its price back above $1.00 for at least 10 consecutive trading days. If it can’t, the stock gets delisted. Many companies resort to reverse stock splits to stay compliant, which is often a red flag for investors.
The NYSE can also begin delisting if a company’s market capitalization or total assets fall below continued listing thresholds, or if the company files for bankruptcy. Delisting is immediate when a bankrupt company fails to meet any of the exchange’s numeric standards. Once delisted, a stock typically moves to the OTC markets, where trading volume, transparency, and investor interest all drop sharply.