Market maker, defined
A market maker is a participant that commits to quoting firm prices on both sides of a market — a price at which it will buy (the bid) and a price at which it will sell (the offer) — and to dealing against orders that arrive at those quotes. Its function is to be a reliable counterparty so that anyone wanting to trade can do so immediately, rather than waiting for another participant to appear on the opposite side. In doing so, the market maker supplies the raw liquidity that a functioning market depends on.
The trade-off is risk. Every fill leaves the market maker holding a position — its inventory — that can move against it before it is offset. Market making is therefore a business of pricing that risk correctly, quoting spreads that compensate for it, and managing exposure continuously. The spread is not an arbitrary fee; it is the price of immediacy and of the inventory risk the market maker absorbs on behalf of everyone else.
How a market maker quotes and profits
The mechanics are straightforward in principle. Suppose a market maker quotes a currency pair with a bid below its offer. A counterparty that wants to sell hits the bid; a counterparty that wants to buy lifts the offer. If the market maker buys from one and sells to another around the same level, it captures the difference between the two prices — the spread — as its gross revenue. That is the core of how a market maker earns.
In reality the two sides rarely arrive perfectly matched. The market maker accumulates inventory — long or short — and must hedge or unwind it in the wider market. It also adjusts its quotes dynamically: widening spreads when volatility or uncertainty rises, skewing them to attract flow that reduces unwanted inventory, and tightening them when competition and calm conditions allow. Profit comes from the spread net of the cost of managing that inventory and of any adverse price moves while positions are held.
Market maker vs liquidity provider vs aggregator
These terms overlap and are often used loosely, but they describe different roles in the chain. A market maker is a specific type of liquidity provider — one that creates prices by quoting a two-sided market. "Liquidity provider" is the broader label for any source of executable prices, which can include market makers, banks and venues. An aggregator does not create prices at all; it collects quotes from many providers and consolidates them into a single, deeper book.
| Role | What it does | How it earns |
|---|---|---|
| Market maker | Creates prices by continuously quoting a firm bid and offer; takes the other side of flow. | Bid-offer spread, net of inventory and hedging costs. |
| Liquidity provider | Any source of executable prices — may be a market maker, a bank or a venue. | Spread and/or commission, depending on the model. |
| Aggregator | Combines many providers' quotes into one deep book and routes orders to the best price. | Markup or commission on aggregated flow; does not quote its own prices. |
Structural distinctions. In practice a single firm can perform more than one of these roles.
Bank vs non-bank market makers
At the top of the FX and broader OTC markets, market making is dominated by two groups. Tier 1 banks have historically been the primary market makers, quoting currency pairs and other instruments to clients and to one another, backed by large balance sheets and deep client franchises. Over the past decade, non-bank electronic market makers — specialist technology-driven trading firms — have become a major force, streaming prices algorithmically at high speed and often competing closely with banks on spread and consistency.
Both matter, and they behave differently. Bank market makers bring balance-sheet capacity and relationship pricing; non-bank market makers bring speed, tight algorithmic pricing and, frequently, willingness to quote in conditions where banks pull back. A resilient liquidity feed blends both, which is why aggregated pools deliberately combine bank and non-bank sources rather than relying on either alone.
Where market makers sit in the Prime of Prime chain
Market makers are the origin of price in the liquidity chain, but most brokers do not connect to them directly. Reaching tier 1 bank and top non-bank market makers requires prime brokerage relationships, credit and scale that are out of reach for smaller firms. This is where a Prime of Prime (PoP) sits between the market makers and the broker: it holds the underlying relationships, aggregates many market-maker quotes into one deep book, intermediates credit, and passes that liquidity through to brokers and their clients.
So the flow runs from bank and non-bank market makers, into an aggregated pool, through a Prime of Prime, and out to the broker and its end clients. For how those quotes are combined, see how FX liquidity aggregation works; for choosing among sources, see how to choose a liquidity provider; and for the terms used here, the glossary.