Key Points
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Interactive Brokers is growing its margin loans at a faster rate than its overall customer base.
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Growing margin loans will help it grow its net interest income.
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Broad interest rates will impact this line item for Interactive Brokers in the years ahead.
In July, Interactive Brokers(NASDAQ: IBKR) proved yet again that it is one of the fastest-growing brokerages in the world. Customer margin loans surpassed $100 billion in July, and were up 49% year over year.
This indicates that the animal spirits of the bull market are in full swing and that Interactive Brokers is capturing significant market share in the financial asset trading space. Here’s why the electronic broker’s margin debt has grown so quickly, and what it means for earnings this quarter.
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Growing customers means growing interest income
In July, the total number of Interactive Brokers customers grew 34% year over year to 5.3 million. The company is attracting increasingly sophisticated customers and professionals to its platform due to its global coverage of financial assets and its low margin-debt rates.
Margin loans offer a way for a brokerage’s customers to bet more aggressively on stocks, as well as the interest charged on short-selling. When the customer base grows, so too will Interactive Brokers’ total margin debt. In fact, last month, it grew much faster than the overall customer count, likely due to aggressive trading in the artificial intelligence (AI) market.
Margin debt growing by 49% year over year is going to provide a huge boost to the company’s net interest income in Q3, at least, if it continues to grow this quickly in August and September. Last quarter, net interest income grew 23% year over year to $1.06 billion. At this rate of margin debt growth, Interactive Brokers should see an acceleration in net interest income growth this quarter.
Image source: Getty Images.
Should you buy Interactive Brokers stock?
One potential headwind to Interactive Brokers’ net interest income would be a decline in interest rates. The company charges interest on clients’ margin loans at a variable rate based on standardized cost-of-borrowing benchmarks such as the Secured Overnight Financing Rate (SOFR). In the last two years, the Federal Reserve has begun to lower its benchmark interest rates, which is a headwind for the company’s net interest income.
Depending on where interest rates head over the next few years, they will be either a headwind or a tailwind for the low-cost broker’s net interest income, which provides the majority of its revenue. Today, the stock trades at a price-to-earnings ratio of 36, which indicates that investors do not believe interest rates will fall in the near future, and that they anticipate that Interactive Brokers will continue to grow its total customer count at a similar pace to previous years. If they are correct on both counts, then Interactive Brokers stock will probably prove a good buy at today’s levels.
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Brett Schafer has positions in Interactive Brokers Group. The Motley Fool has positions in and recommends Interactive Brokers Group. The Motley Fool recommends the following options: long January 2027 $43.75 calls on Interactive Brokers Group and short January 2027 $46.25 calls on Interactive Brokers Group. The Motley Fool has a disclosure policy.
