Ok, I'm going to make this very clear, short and concise, every risk I can think of off the top of my head related to EFPs: 1) Mark to market risk. If the stock goes up, you're now up on the stock, and down on the future. The future gets marked to the market. This can cause you to have a negative cash balance. This also works the other way 2) Spread risk. Let's say the stock is 100, interest rates are 5%. A SSF 1 year out will be 105, assuming zero dividends, and ignoring the bid-ask spread. This $5 is the spread between the stock and the future. IF the stock shoots to $1000 tomorrow.. The interest rate is still 5%, and the SSF is still approximately 1 year out (364 days, but for this example we're going to ignore that). The SSF will now be $1050.. a $50 spread. This means you lost $45 (and you WILL have to unwind the position, since the future will be marked to the market and you will have a huge debit balance). Of course, this is an extreme example, but gaining or losing 50% on the spread is certainly a possibility (look at AMZN!). This is very closely correlated with mark to market risk. 3) Liquidity (and the bid-ask spread). The spread on the future is much wider then the spread on the stock. This means every time you adjust, you will lose a few cents per share (and since you're not getting THAT much in interest to begin with, this IS significant) 4) Significant changes in dividends. If your 2% dividend paying stock suddenly stops paying the dividends. The SSF value will go up to reflect this, even if the stock value doesn't move. This is because the future takes into account dividends. 5) Significant changes to the cost to borrow a stock. If a stock suddenly lands on the SHO list, I guarantee you the future value will go DOWN if the stock price does not move. This is because the stock is more expensive to borrow. The counterparty to your EFP must take the opposite position you do. If they have to pay more to short the stock, they won't offer as good of a yield on the EFP. Of course, EVERY RISK goes BOTH WAYS. You can see a loss or a windfall profit. EFPs are NOT risk free and are NOT simply a way to earn the best interest on your money. It is definitely a GOOD way, but BE AWARE of the risks involved! Oh, and one last thing, Don't bother trying to complain to IB that they didn't properly disclose the risks of an EFP. You have to request permission to trade Single Stock Futures, and in doing so you acknowledged that you know the characteristics and risks of futures contracts. Well, these elements I listed above are the risks of single stock futures, if you didn't know them, and lost money as a result, chalk it up to experience and learn from it Everybody makes mistakes!