Which stock brokerage firm has the lowest broker call rates for margin accounts over 5000000?

Broker call rates can vary frequently based on market conditions and specific brokerage policies, so it's essential to check current rates directly from firms. As of my last update, firms like Interactive Brokers and Charles Schwab are known for competitive margin rates, especially for higher account balances. However, for the most accurate and up-to-date information, I recommend visiting the individual brokerage websites or contacting them directly.