Interactive Brokers Group, Inc. (Nasdaq: IBKR), a leader in automated global electronic brokerage, has unveiled its impressive monthly performance metrics for September 2025. The company reported a remarkable increase in its Daily Average Revenue Trades (DARTs), achieving 3.864 million—a staggering 47% increase compared to the previous year and an 11% rise from the previous month. This upward trend underscores the growing engagement of clients in trading activities.

2. Surging Client Equity and Margin Balances

The financial health of Interactive Brokers continues to show substantial improvement, with client equity reaching an impressive $757.5 billion, marking a 40% increase year-over-year and a 6% rise from August. Additionally, the company reported a significant increase in client margin loan balances, which stood at $77.3 billion—39% higher than the previous year and up 8% from the prior month. This growth in margin loans indicates increased leverage utilization by clients, reflecting their confidence in the market.

3. Expanding Client Base

The client account base for Interactive Brokers has shown robust growth, reaching 4.127 million accounts—up 32% year-over-year and 2% from the previous month. Notably, September saw the addition of 111,900 real accounts; however, this growth was offset by the withdrawal of one introducing broker, which accounted for 38,800 accounts and $413.5 million in customer assets. The firm anticipates an additional 2,900 account closures in the upcoming period as part of this transition.

4. Commission Trends and Trading Expenses

Interactive Brokers reported an average commission of $2.71 per cleared Commissionable Order, which includes exchange, clearing, and regulatory fees. The detailed breakdown of commissions revealed that the average commission for stocks stood at $2.01 for 1,001 shares, while equity options and futures averaged $3.95 for 6.8 contracts and $4.44 for 3.1 contracts, respectively.

5. September Performance Highlights

The metrics for September 2025 highlight several key performance indicators:

Daily Average Revenue Trades (DARTs): 3.864 million (47% year-over-year increase)

Ending Client Equity: $757.5 billion (40% year-over-year increase)

Ending Client Margin Loan Balances: $77.3 billion (39% year-over-year increase)

Ending Client Credit Balances: $154.8 billion (33% year-over-year increase)

Client Accounts: 4.127 million (32% year-over-year increase)

Annualized Average Cleared DARTs per Client Account: 203

6. Mark to Market and Currency Diversification

In a detailed review of other financial information, Interactive Brokers noted a mark to market loss of $195,000 on its U.S. governmental securities portfolio for the quarter ending September 30. Additionally, the value of the company's GLOBAL reporting, based on a basket of 10 major currencies, experienced a slight increase of 0.02% in September, but decreased by 0.25% for the quarter.

7. Cost of Trade Execution for IBKR PRO Clients

In a push for transparency, Interactive Brokers quantified the all-in cost of trade execution for its IBKR PRO clients. For the month of September, the average cost of executing U.S. Reg.-NMS stock trades was approximately 1.8 basis points of trade money, with a rolling twelve-month net cost of 2.9 basis points.

8. Conclusion

Interactive Brokers Group's September performance metrics demonstrate a solid growth trajectory across multiple key indicators, reflecting the firm's strong standing in the brokerage industry. The significant increases in trading activity, client equity, and account growth highlight the company's ability to attract and retain clients in a competitive market. As Interactive Brokers continues to innovate and enhance its trading platform, it positions itself for sustained growth and success in the evolving financial landscape.

Original press release