Market makers are firms registered with exchanges and regulators to continuously quote both a buying price and a selling price for specific securities, standing ready to trade with you throughout the day and earning the small gap between those two prices. They are the reason a market order for a common stock fills in milliseconds instead of waiting for another investor to appear on the other side. Some are dedicated to particular listed companies on the New York Stock Exchange, some are high-speed electronic firms handling millions of retail orders, and some are trading desks inside large investment banks. What they share is an obligation to keep quoting, in size, even when the market is uncomfortable.
What Market Makers Actually Do
Liquidity is what lets you sell a stock almost instantly at a price close to the last trade. Market makers create that liquidity by continuously posting prices at which they will buy from you or sell to you. When you submit a market order, it does not sit in a queue hoping someone else happens to want the other side. A market maker fills it.
This matters most during periods of stress. When bad news hits and many investors want to sell the same stock, market makers absorb that pressure by buying shares into their own inventory. They take a real financial risk doing so, but their presence prevents the kind of cascading price gaps that would make investing feel like gambling. The payoff for the market as a whole is tighter spreads, faster fills, and more confidence that you can exit a position when you need to.
The Main Types of Market Makers
Designated Market Makers on the NYSE
On the New York Stock Exchange, Designated Market Makers are assigned to specific listed companies and carry formal obligations to maintain orderly trading. DMMs display quotes in the exchange’s order book and commit capital during the opening and closing auctions, the highest-volume moments of the day. Human judgment still plays a role at the open, where overnight news creates pricing uncertainty and the DMM helps establish a fair opening price that minimizes early volatility.1NYSE. Designated Market Makers (DMMs) Improving Liquidity and Market Quality
Electronic Market Makers and Wholesalers
Firms like Citadel Securities and Virtu Financial dominate modern equity market making through high-frequency algorithms that adjust quotes in microseconds. They operate on exchanges and also off-exchange as “wholesalers,” executing retail orders routed to them directly by brokerages rather than through a public exchange. Wholesalers fill those orders at prices inside the national best bid and offer, giving retail investors a small amount of price improvement compared to the displayed exchange price. That model gives them access to a large share of retail trading volume.
Investment Banks
Large institutions like Goldman Sachs and Morgan Stanley make markets through internal trading desks, typically in instruments that are harder to trade electronically. Corporate bonds, options, and foreign currencies often require human negotiation and larger capital commitments than equities. Where electronic firms focus on speed and volume in stocks, investment banks tend to handle bigger, more specialized institutional orders where the spread is wider and the holding period longer.
How Market Makers Make Money
The Bid-Ask Spread
The core revenue source is the difference between a market maker’s bid and its ask. If a firm bids $50.00 for a stock and offers to sell at $50.02, that two-cent spread is the gross profit on a round trip. Because these firms handle millions of shares daily, even a penny of spread captured thousands of times adds up to serious money. The risk is real. If a market maker buys at $50.00 and the price drops to $49.95 before it can sell, it eats the loss. Sophisticated software adjusts quotes in real time to keep net exposure low, and high volume smooths out individual losing trades.
Exchange Rebates
Exchanges also pay market makers for posting quotes that add liquidity to the order book. Under the “maker-taker” pricing model, a firm that posts a resting order receives a small rebate when that order gets filled, while the firm that sends an order removing that liquidity pays a fee. The Investors Exchange, for example, offers displayed liquidity rebates ranging from free at the lowest volume tier up to $0.0023 per share for firms adding at least 40 million shares of displayed liquidity per day.2Securities and Exchange Commission. Notice of Filing and Immediate Effectiveness of Proposed Rule Change to Amend the Exchange Fee Schedule Concerning Equities Transaction Pricing Small per share, meaningful at scale, and the tiered structure rewards the firms providing the most liquidity.
The Rules That Keep Them Quoting
Regulators impose continuous obligations designed to make sure market makers actually provide the liquidity they registered to provide, rather than cherry-picking profitable moments.
The Two-Sided Quote Obligation
Both Nasdaq and FINRA require registered market makers to maintain a continuous two-sided trading interest during regular market hours. That means posting both a bid and an offer for every security in which they are registered, and replenishing those quotes after each execution.3Nasdaq. Nasdaq Equity 2 Market Participants – Section 5 Market Maker Obligations FINRA’s Rule 6272 imposes the same requirement for ADF-eligible securities.4FINRA.org. FINRA Rule 6272 Character of Quotations
The obligation is suspended during formal trading halts, pauses, and suspensions, and does not resume until after the first regular transaction on the primary listing market following the halt.3Nasdaq. Nasdaq Equity 2 Market Participants – Section 5 Market Maker Obligations Market makers are not required to quote into a halt, but they are expected to stay in the market through ordinary volatility that does not trigger a formal pause.
Quote Width and Size
A market maker cannot satisfy its obligation by posting absurdly wide quotes. FINRA sets maximum percentages for how far a bid or offer can sit from the national best bid or offer. For stocks in the S&P 500 or Russell 1000, the initial quote must be within 8% of the NBBO during core hours, widened to 20% during the first and last minutes of trading. For other stocks priced at $1 or above, the limit is 28%.4FINRA.org. FINRA Rule 6272 Character of Quotations On Nasdaq, each quote must display at least one standard round lot.3Nasdaq. Nasdaq Equity 2 Market Participants – Section 5 Market Maker Obligations
Penalties
Failing to meet these obligations exposes a firm to censure, fines, suspension, or revocation of its market maker registration.3Nasdaq. Nasdaq Equity 2 Market Participants – Section 5 Market Maker Obligations FINRA’s published sanction guidelines give a sense of scale: for quality-of-markets violations like best execution failures, small firms face fines of $10,000 to $310,000, while midsize and large firms face fines starting at $50,000 with no stated upper limit. For violations like trading ahead of customer orders, fines range from $5,000 to $310,000.5FINRA.org. FINRA Sanction Guidelines Enforcement actions involving market manipulation or widespread harm have produced penalties well into the millions.
Where Your Retail Order Actually Goes
When you place a stock order through a retail brokerage, it likely does not go to an exchange at all. It goes to a wholesale market maker that pays your broker for the right to execute it. This arrangement, payment for order flow, is how firms like Citadel Securities and Virtu Financial get access to retail orders. The wholesaler fills your order at a price slightly better than the exchange quote and keeps the rest of the spread. Your broker gets paid for routing the order, which is one reason many brokerages charge zero commissions.
The SEC considered overhauling this system through a proposed Order Competition Rule that would have required retail orders to be routed through exchange-based auctions, but the Commission formally withdrew that proposal in June 2025 along with its proposed Regulation Best Execution.6U.S. Securities and Exchange Commission. Order Competition Rule Payment for order flow remains legal.
What You Can Actually See
Existing Regulation NMS rules require meaningful disclosure. Rule 605 requires market centers to publish monthly reports on execution quality, including fill speeds and price improvement statistics. Starting in November 2026, updated Rule 605 requires those reports to calculate price improvement relative to the best available displayed price, making it easier to compare execution quality across venues.7SEC.gov. Extension of Compliance Date for Disclosure of Order Execution Information Rule 606 separately requires brokers to disclose where they route orders and any payments they receive for doing so, giving you visibility into potential conflicts.8eCFR. 17 CFR Part 242 – Regulation NMS Regulation of the National Market System
A Note on Crypto
Firms providing liquidity on crypto trading platforms operate in a regulatory environment still taking shape. As of February 2026, the SEC’s Division of Trading and Markets has issued guidance indicating that platforms trading crypto asset securities must comply with Regulation ATS, including filing Form ATS or Form ATS-N. For broker-dealers holding stablecoin positions, the SEC staff will not object to applying a 2% haircut of market value when calculating net capital, rather than treating the position as having no ready market.9U.S. Securities and Exchange Commission. Division of Trading and Markets Frequently Asked Questions Relating to Crypto Asset Activities and Distributed Ledger Technology
In practice, many crypto market makers operate outside the traditional broker-dealer framework, particularly when providing liquidity for tokens the SEC has not classified as securities. That gap means fewer enforceable obligations around continuous quoting, capital adequacy, and fair execution than equity market makers face. For an investor deciding between trading stocks and trading crypto, the absence of the regulatory infrastructure described above is one of the meaningful differences.