A news brief titled, "Interactive Brokers offers additional security for uninvested cash held in brokerage accounts" tells us, "Interactive Brokers LLC offer IBKR Pro clients with individual accounts and/or IRAs and organizational accounts a program that gives them additional security on the cash held in their brokerage accounts. As of May 27, 2025, the Insured Bank Deposit Sweep Program provides up to USD 5.0 million of Federal Deposit Insurance Corporation (FDIC) coverage on an individual or institutional account's free cash balances. In addition, joint accounts are eligible for up to USD 10.0 million in coverage on free cash balances." They explain, "Combined with the existing Securities Investor Protection Corporation (SIPC) coverage of the first USD 250,000 in your brokerage account, the total available insurance for your IBKR brokerage and sweep accounts is USD 5.25 million for individual accounts and USD 10.25 million for joint accounts. Cash balances above these limits remain subject to safeguarding under the SEC's Customer Protection Rule 15c3-3, backed by the firm's equity capital. Adding this program will not disrupt your account features or your trading capabilities. You will continue to earn competitive interest on balances, and your account cash will remain available for stocks, options, futures, currencies and bond trading on more than 160 markets globally."