What is a market maker?

Without these participants, markets would be slower, less efficient, and potentially more expensive for everyday investors. This guide explains what market makers do, how they operate, and why their presence matters to anyone who invests or trades in UK financial markets.

Market makers explained in simple terms

A market maker is a firm or individual that commits to buying and selling a particular financial instrument on a continuous basis. They quote both a price at which they will buy from you and a price at which they will sell to you, at virtually any time during trading hours.

Think of a market maker like a used car dealer who always has stock and always wants to buy more vehicles. The dealer offers one price when purchasing your car and a slightly higher price when selling a similar vehicle to someone else. The difference between these two prices represents their potential profit margin.

In financial markets, what is market making in practice? It means committing capital and taking on inventory risk to ensure that buyers and sellers can transact whenever they wish. Market makers do not match buyers directly with sellers. Instead, they act as the counterparty to both sides, absorbing temporary imbalances between supply and demand.

What do market makers actually do?

The core functions of market makers can be broken down into two essential activities that keep markets running smoothly.

Providing liquidity

Liquidity refers to how easily an asset can be bought or sold without significantly affecting its price. Market makers provide this liquidity by maintaining an inventory of securities and standing ready to trade at any moment.

When you submit an order through your broker, you generally expect it to execute quickly. Market makers make this possible. Without them, you might place a sell order and wait hours or even days for a willing buyer to appear, potentially at a much lower price than you anticipated.

Quoting bid and ask prices

Market makers continuously quote two prices for each security they cover:

The gap between these two figures is called the spread. A narrower spread generally indicates a more liquid market, while wider spreads suggest lower liquidity or higher volatility.

What do market makers do to maintain these quotes? They constantly monitor order flow, adjust prices based on supply and demand, manage their inventory, and respond to market-moving news. This work requires sophisticated technology, substantial capital, and careful risk management.

How do market makers make money?

How do market makers make money if they are providing a service to other traders? Their primary income source is the bid-ask spread itself.

When a market maker buys a share at £9.98 and sells it at £10.02, they capture £0.04 per share. Multiplied across thousands or millions of transactions daily, these small amounts accumulate into meaningful revenue.

However, this business model carries genuine risks. If a market maker holds shares and the price drops sharply, they face losses. They must also commit significant capital to maintain inventory and meet their obligations to quote prices continuously.

Market makers do not guarantee profits for themselves, and their activities certainly do not guarantee profits for investors trading with them. Markets can move against anyone, regardless of their role.

Types of market maker

Different market structures have different types of market makers, each with specific responsibilities and characteristics.

Designated market makers

A designated market maker holds a formal appointment from an exchange to maintain fair and orderly trading in specific securities. On exchanges like the New York Stock Exchange, designated market makers have obligations to step in during periods of unusual volatility or imbalance.

These firms accept enhanced responsibilities in exchange for certain privileges, such as access to order flow information or reduced trading fees. The designated market maker role exists to ensure that even during stressful market conditions, there remains a party willing to provide liquidity.

Institutional and electronic market makers

Beyond designated roles, who are market makers in the broader sense? They include:

• Large investment banks that make markets in various instruments as part of their wider operations

• Specialist proprietary trading firms focused exclusively on market making

• Electronic market makers using algorithmic systems to quote prices across multiple venues simultaneously

Electronic market making has grown substantially with technological advances. These firms use automated systems to process information, adjust quotes, and execute trades in fractions of a second. They operate across equities, bonds, currencies, and derivatives.

Why market makers matter for everyday investors

Even if you never interact directly with a market maker, their presence shapes your investing experience in several ways.

When you buy shares through an investment platform, the price you pay reflects the market maker's ask price. Competitive market making tends to keep this spread narrow, reducing your transaction costs. In less liquid markets with fewer market makers, spreads widen, and trading becomes more expensive.

Market makers also contribute to price discovery, the process by which markets determine the fair value of securities. By continuously adjusting their quotes based on new information, they help prices reflect available knowledge about a company or asset.

Market makers and risk: what you should know

While market makers provide valuable services, their presence does not eliminate investment risk. Several points deserve careful consideration.

Market makers are commercial entities pursuing profit. Their quotes reflect their assessment of value and risk, not necessarily the true or fair price of a security. During periods of severe volatility, spreads can widen dramatically as market makers protect themselves from rapid price movements.

In the UK, the Financial Conduct Authority regulates firms operating as market makers. This regulation covers conduct standards and capital requirements, but it does not guarantee that markets will always function smoothly or that investors will avoid losses.

Some trading strategies attempt to exploit or anticipate market maker behaviour. However, market makers possess informational advantages and technological capabilities that individual investors typically cannot match. Attempting to trade against professional market makers rarely ends well for retail participants.

Summary

Market makers serve as essential intermediaries in financial markets, providing liquidity by standing ready to buy and sell securities continuously. They quote bid and ask prices, earning potential profit from the spread between these figures.

Different types exist, from designated market makers with formal exchange responsibilities to electronic firms operating across multiple venues. Their activities generally benefit everyday investors through tighter spreads and faster execution, though this comes with no guarantee of favourable prices or outcomes.

Understanding what a market maker does helps you appreciate the mechanics behind every trade you place. Markets are not abstract systems but networks of participants with different roles, incentives, and capabilities. Market makers occupy a central position in this network, facilitating the transactions that allow investors to build and adjust their portfolios.

For informational purposes only. This article does not constitute investment advice. Investing and trading involve risk, and you may lose some or all of your capital.