Unless I'm reading their website wrong, it looks like they are currently paying 0%. According to this, their current Benchmark (BM) is 0.21%: http://www.interactivebrokers.com/en/accounts/fees/monthlyInterestRates.php?ib_entity=llc According to this, the interest they pay on Tier 1 balances (balances between $10k and $100k) is currently BM-0.5% and the interest they pay on Tier 2 balances (balances greater than $100k) is currently BM-0.25%... both come out to a negative number... so basically 0%: http://www.interactivebrokers.com/en/accounts/fees/interest.php?ib_entity=llc Here is more information on how they calculate monthly interest: http://www.interactivebrokers.com/en/accounts/fees/interestMethods.php?ib_entity=llc#calculations If anyone else reads this differently, feel free to disagree.
It is generous of IB to not pay us negative interest (e.g. charge us) for our unused funds. Also nice of them to add mutual funds but avoid any and all money market funds, so you have no chance to get any return on those funds.
I've seen posts on this and I realize they're available but I have several IRAs there and this seems like an awfully big pain. I'd prefer to just buy a money market fund and forget about it. I'll likely transfer half my funds to Fidelity where I can get a decent rate of return, and use the canadian money market ETF for the rest of my funds (that aren't being used as margin for futures positions). Then the only problem is hedging moves in CAD...