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Does Interactive Brokers Pay Interest on Cash? (IBKR Cash Interest Explained)

Last updated: 14 June 2026 · By Spencer Li, CFTe

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Yes, Interactive Brokers (IBKR) pays interest on the spare cash sitting in your account, but only on cash that has settled and stayed put for a while, and only above a minimum balance. Accounts holding more than USD 100,000 in long-settled cash earn the full posted interest rate, and smaller accounts earn a rate proportional to their size, so the more idle cash you hold, the closer you get to the full rate. Interest accrues daily and IBKR pays it once a month, on the third business day of the following month. It is automatic. You do not subscribe, click anything, or move your cash into a separate product to receive it. The one thing worth knowing up front: a few currencies are treated differently, and cash held in JPY or RUB can actually earn a negative rate, while some other currencies earn 0%.

So your money does not sit idle between trades. Here is exactly how the interest works, who qualifies for the full rate, and the currency traps to watch.

How does IBKR cash interest work?

IBKR pays interest on “long-settled” cash, which means cash that has cleared and been sitting in your account, not money you deposited yesterday or freed up from a trade that has not settled yet. The idea is simple. While your cash waits between trades, IBKR pays you a yield on it rather than letting it earn nothing.

Two numbers shape what you actually receive:

• Your balance. Above USD 100,000 of long-settled cash, you earn the full posted rate. Below that, you earn a rate proportional to your balance, so a smaller account earns a smaller slice of the full rate.
• The posted rate itself. This is set by IBKR and moves with the market, so the headline figure today will not be the figure next year. Always check the live rate on IBKR’s own site rather than any number you read in a blog post, including this one.

Interest accrues daily and is posted monthly, on the third business day of the following month. So the interest you earn across, say, June shows up in your account in early July.

Who qualifies for the full interest rate?

Anyone can earn interest, but the full posted rate kicks in at USD 100,000 of long-settled cash (or the equivalent in another currency). Below that line, you still earn, just at a proportional rate.

Here is the tiered picture in one view.

Long-settled cash balance	What you earn	Notes
Above USD 100,000	Full posted interest rate	The rate IBKR publishes, set by the market
Below USD 100,000	A rate proportional to your balance	Smaller balance, smaller slice of the full rate
Held in JPY or RUB	Can be a negative rate	You may pay rather than earn on these
Certain other currencies	0%	No interest credited

Do note that these are policy thresholds IBKR sets, and a broker can change its own policy. Treat the structure as the durable part and the exact rate as the moving part.

What is the auto-swap program?

There is a second, more advanced layer for larger accounts. If you hold both large long and large short cash positions across different currencies, IBKR offers an auto-swap program. You authorize IBKR to execute the forex transactions that net those positions against each other, which improves your overall interest benefit and lowers your interest cost.

This one is not for most retail traders. The auto-swap program is only open to qualifying investors with cash balances of at least USD 10 million or equivalent, or to those who qualify as an Eligible Contract Participant (ECP, a US regulatory category for large or sophisticated market participants). If you are reading this to figure out the interest on a few thousand dollars of idle cash, this layer simply does not apply to you, and that is fine.

The currency trap to watch

Most people assume “interest on cash” can only ever be a good thing. Not always. Cash held in JPY or RUB may receive a negative rate, which means you can be charged rather than paid for holding it. Other currencies may earn 0%.

This matters more than it sounds. If you trade globally through IBKR, your cash can end up parked in a currency you did not consciously choose, simply as the by-product of your last few trades. Personally, I keep an eye on which currency my idle cash is actually sitting in, because the interest treatment follows the currency, not your intentions.

Cash interest vs parking cash in T-Bills

Earning interest on idle cash is the passive, do-nothing option. The active alternative, if you want your spare cash working harder, is to park it in short-dated US Treasury Bills (T-Bills) inside the same IBKR account. T-Bills behave almost like cash because they are so short-dated, but they let you lock in a known yield to maturity rather than a floating cash rate. I walk through the exact steps in how to buy US T-Bills on Interactive Brokers.

Which one is “better” is not really the question. The cash rate is effortless and floating. The T-Bill is a small, deliberate action that fixes your yield. A scanner can tell you both rates in a second. It will not tell you whether your trading plan needs that cash liquid next week, which is the judgment call that decides between them. That judgment, deciding when idle cash should stay liquid and when it should be put to work, is the part no tool trades for you.

Tips from the trading desk

• The interest is automatic. You do not need to enrol, so there is nothing to set up beyond holding cash in the account.
• Watch the currency your idle cash sits in, not just the amount. JPY and RUB can turn the interest negative.
• Remember the settlement delay. Only long-settled cash earns, so freshly deposited or just-freed cash does not start earning immediately.
• The rate moves. Check IBKR’s live figure rather than trusting any quoted number, including the ones above.

FAQ

Does Interactive Brokers pay interest on uninvested cash?
Yes. IBKR pays interest on long-settled cash (cash that has cleared and been sitting in the account). Balances above USD 100,000 earn the full posted rate, and smaller balances earn a rate proportional to their size.

How much do you need in IBKR to earn the full interest rate?
You need more than USD 100,000 of long-settled cash, or the equivalent in another currency, to earn the full posted rate. Below that threshold you still earn interest, just at a proportional rate.

When does IBKR pay the cash interest?
Interest accrues daily and is paid out monthly, on the third business day of the following month. So a month’s interest appears in your account early in the next month.

Can IBKR cash interest be negative?
Yes, for some currencies. Cash held in JPY or RUB may receive a negative rate, meaning you are charged rather than paid, and some other currencies earn 0%.

What is the IBKR auto-swap program?
It is an advanced program for large accounts. You authorize IBKR to execute forex transactions that net your long and short cash positions to improve your overall interest, but it is only available to qualifying investors with at least USD 10 million in cash, or those who qualify as an Eligible Contract Participant (ECP).

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That is the whole picture on IBKR cash interest. If you have not opened the account yet, start with the pillar: Interactive Brokers (IBKR) for Beginners: A Complete Guide.

Want a trading routine that fits around a day job? Grab the free 15-Minute Swing Trading Starter Kit. It is the exact once-a-day process I use to scan and trade any market in 15 minutes.

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About the author. Spencer Li is the founder of Synapse Trading and a Certified Financial Technician (CFTe) with 15 years of trading across stocks, forex, crypto, commodities, and bonds. His trade log is public, 404 trades, losses left in. He teaches low-risk swing trading in 15 minutes a day, one system for any market.

Education, not financial advice. Synapse Trading is not licensed by MAS to advise on investment products. Trading carries risk of loss; past performance is not indicative of future results.

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Related

Interactive Brokers for Beginners (pillar) · How to buy US T-Bills on IBKR · Deposit and withdraw on Interactive Brokers · Open and set up an Interactive Brokers account

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