Why do I need a Cash Account to open a Brokerage Account?

In order to use Wealthfront’s Brokerage Account, you must also have a Wealthfront Cash Account. The funds in your Cash Account will be used to purchase securities in your Brokerage Account, and when you sell securities, the proceeds will be swept to your Cash Account.

It is standard for brokerage firms to give clients a place to store their cash that they are preparing to invest. At Wealthfront, the Cash Account serves this purpose. Your Cash Account comes with a high Annual Percentage Yield (APY) and FDIC insurance eligibility through program banks. More details can be found  here.