Citadel Securities generated approximately $7.3 billion in trading revenue during the second quarter, the electronic market maker's best quarter on record and a result that makes its already strong first quarter look modest by comparison. The firm posted about $4.3 billion in the first three months of the year.

The record performance was driven by surging retail investor activity and all-time highs in both US equity and options trading volumes.

Inside the numbers

Founded by billionaire Ken Griffin, Citadel Securities has historically commanded roughly 25% of all US equity trading volume, making it one of the largest market makers in the world. Its business model is simple in concept: stand between buyers and sellers, capture the bid-ask spread, and repeat the process billions of times across millions of securities. A large share of that activity comes from retail brokers such as Robinhood and Charles Schwab, which route customer orders to wholesale market makers under payment-for-order-flow arrangements — a practice that has long drawn regulatory scrutiny.

Cash equity volumes in May reportedly exceeded prior peaks by more than 10%, while options premium trading reached new highs in June. The firm's first-quarter revenue of $4.3 billion had already marked a 27% increase year-over-year.

The scale of the second quarter becomes clear when set against 2024: Citadel Securities reportedly generated $9.7 billion in net trading revenue for the entire year, meaning the firm just matched roughly 75% of a full year's haul in a single quarter.

A broader non-bank trading boom

Citadel Securities is not the only non-bank trading firm thriving at the moment. Rivals such as Jane Street, which posted record results of its own in 2024, and Hudson River Trading have also reported strong performance amid similar market conditions, though neither has matched the sheer scale of Citadel's quarterly haul. The boom reflects a structural shift in market plumbing: off-exchange venues, where wholesalers internalize retail orders away from public exchanges, regularly account for more than 40% of daily US equity volume.

Digital assets: present but not the story

The firm does maintain a specialized digital assets team and has made investments in major crypto exchanges, including Kraken and Crypto.com. However, its record second-quarter performance was driven by traditional equity and options markets, not cryptocurrency activity.

What this means for markets

For regulators, these numbers are likely to fuel ongoing debates about market structure. The concentration of order flow through a small number of market makers has been a recurring concern, particularly around payment for order flow and the question of whether retail investors are getting the best possible execution on their trades. Griffin himself testified before Congress on these issues during the 2021 GameStop trading frenzy, and the SEC later proposed rules aimed at wholesale market makers' execution practices, though none were ultimately adopted.

Citadel Securities operates privately, so investors cannot buy shares directly, and reports on its performance typically emerge from unnamed sources acquainted with the firm's activities. Griffin has said in the past that an eventual public listing is possible, which would subject the firm to regular public disclosure for the first time, though he has set no timetable.