High-Frequency Trading Explained: The Firms, Strategies, Roles, and Salaries Inside the $114 Billion Industry
Citadel Securities cleared $9.7bn and Jane Street $20.5bn last year. Here is how the largest electronic market makers operate and what they pay the people who build them.
$114 billion. That figure is the combined trading revenue the largest non-bank trading firms produced last year, and it now represents close to one-fifth of the entire global trading revenue pool that the major investment banks once controlled almost outright. Citadel Securities recorded $9.7bn in revenue against $4.2bn of net income. Jane Street reported net revenues near $20.5bn while capturing more than 10% of all US equity volume.
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Today’s breakdown covers the full high-frequency trading industry, written for readers who already hold the basics. What follows is a working brief on what HFT really is, who runs it, how the profit gets made, which seats exist inside these firms, and what each one pays from the internship band through to senior compensation in the seven figures.
The numbers behind these firms are private and closely guarded, so the figures throughout come from regulatory filings, credit reports, and disclosed revenue. The detail worth holding onto before you read is the share migration underneath the headline revenue, where Citadel Securities and Jane Street keep pulling retail wholesaling and ETF flow away from older incumbents at a measurable pace.
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What HFT Actually Is
High-frequency trading is a branch of automated trading defined by three characteristics that hold across nearly every firm in the space. The first is the holding period, which runs from microseconds to seconds, with most positions closed out by the end of the trading day and overnight inventory treated as the exception. The second is the profit profile, where each individual trade earns a fraction of a cent per share and the edge comes from repeating that capture across millions of trades. The third is the role of latency, which sits at the center of everything because the speed of light through fiber and copper sets a hard floor on how fast information can move, and firms spend enormous sums getting as close to that floor as the physics permits.
A point of accuracy is worth setting down early. The most prominent names in this group are described more precisely as proprietary trading firms or electronic market makers. Jane Street in particular trades with holding periods and balance-sheet commitments that look quite different from the classic microsecond-scalping model, yet most press coverage still files it under the HFT heading. The label has hardened into a catch-all for any fast, automated, non-bank trading operation, which has the effect of flattening the real differences in how these firms carry and price risk. Keeping that distinction in view changes how you read almost everything written about them.
The Big Players
Because nearly all of these firms are private and guard their numbers closely, the figures below come from regulatory filings, credit reports, and disclosed revenue, so the ordering should be read as approximate rather than precise.
At the top by both scale and public profile sits Citadel Securities, founded by Ken Griffin and now headquartered in Miami. It is the largest US equity market maker, handling somewhere around one in four US-listed equity shares and a commanding share of the retail order flow that brokers such as Robinhood route to it. Its first-half 2024 net trading revenue climbed 81% to $4.9bn, and at year-end 2024 it held net capital roughly $3.42bn above the required regulatory minimum, which gives a sense of how much risk capital the firm chooses to carry.
Jane Street, based in New York, built its reputation in ETF market making and has since become a major force in listed options, trading close to 1 billion OCC contracts in 2024 for roughly 8% of all cleared options volume. Its first-half 2024 net trading revenue rose 78% to $8.4bn, and reported average compensation across the firm sits near $1.4M per year, a number that blends everyone from first-year hires up to senior partners and should be read with that spread in mind.
Behind those two are several firms that operate at comparable sophistication even when their revenue runs smaller. Jump Trading in Chicago works across futures, options, and a substantial crypto book, and remains one of the most opaque firms in the industry, having had its rating outlook raised by agencies last year. Hudson River Trading, known as HRT, runs research-driven equities and multi-asset strategies out of New York and issued a $2.35bn senior secured term loan due 2030 in late 2024 to refinance existing debt and fund the growth of its trading book. XTX Markets in London, founded by Alex Gerko, leans heavily on statistical and machine-learning models in foreign exchange and has grown into one of the largest currency liquidity providers in the world. Optiver and IMC, both rooted in Amsterdam with large Chicago operations, specialize in options market making, and IMC reported 2025 revenue of $3.12bn with net income of $968m, up from $686m the prior year.
The next layer carries names that quant candidates encounter constantly during recruiting. DRW in Chicago, founded by Don Wilson, runs a broad multi-asset proprietary book. Tower Research Capital, started by Mark Gorton, is one of the older firms in the field. Susquehanna, often referred to as SIG, helped pioneer listed equity options market making. Two Sigma Securities operates the market-making arm tied to the well-known quant fund, while Flow Traders focuses on exchange-traded products out of Amsterdam, and Virtu Financial, listed under the ticker VIRT, stands as the one large publicly traded member of the group.
The underlying story across all of these names is the steady migration of market share. Citadel Securities and Jane Street have been pulling retail wholesaling and ETF flow away from the older incumbents at a measurable pace. Susquehanna’s payment for order flow in the retail options channel has slipped to about one-third of Citadel Securities today, having stood at roughly two-thirds only five years ago. Market position in this industry turns heavily on infrastructure quality and pricing, and it shifts faster than it does in almost any other corner of finance.
