Why did IBKR liquidate some of my positions without first notifying me?

Please note, Interactive Brokers does not make margin calls, as liquidations occur in real-time. Generally, accounts will not have time to deposit funds to meet a margin deficiency.

However, if you wish to send in funds to cover a deficit, it will likely benefit you most to send in enough funds to give yourself a cushion above your current deficit…

An Intraday Margin Deficit (IMD) could occur when a maintenance margin deficiency exists at the time of, or immediately after, any of the following transactions in a margin account:

• Any purchase or sale effected in the account, including as the result of the exercise or assignment of an option, that has the effect of reducing the account’s excess liquidity…

When you open a margin account you have the ability to borrow from IBKR. You can not set a limit or a set only a specific amount of margin to use in a margin account. If the account has sufficient Available Funds then a new order would be accepted. There is a calculated margin requirement for positions in a margin type account displayed as an Initial margin and Maintenance margin requirement. In addition to contracts traded in the account any borrowed cash from Forex trading or from trading outside the account’s Base Currency can have a calculated margin requirement. There are tools available so you can monitor your account’s margin requirements and cash balances in real time or as a daily snapshot…

The amount of stock required to be closed when the account is in a margin deficit depends on the account type and the open positions held in the account. For example, if you have a Reg T margin account and have an SMA deficit of USD -1,000 USD, you will need to close USD 2,000 of marginable stock to get SMA back to zero and make the account Reg T compliant. For a USD -1,000 deficit in a Portfolio Margin account (assuming all stock positions have a margin requirement of 15%), you will need to close approximately USD 6,700 of marginable stock. Please note, open positions in your account can have different margin requirements, so we recommend using the Check Margin Impact feature to preview the change in the account's margin requirements before submitting an order. Review the amount in the "Change" column to see if an order will increase or decrease the account's total Maintenance Margin requirements. …