Suppose you hold $10,000 CAD and $0 USD in your margin account and you decide to buy $5,000 of a U.S. stock. After purchase, your USD balance will be negative for the total cost of the trade ($5,000USD+plus commissions), and your CAD balance will remain at $10,000.
While the buy order is settling (as mentioned above), you can place a request manually to exchange CAD cash to cover the USD debt balance as this will not happen automatically. The two-day settlement period can be treated like a grace period; it gives you the opportunity to cover your debt without being charged interest.
If you don’t end up exchanging your CAD funds to cover the negative $5,000 USD, Questrade will begin to charge you interest once the trade settles on the amount you’re borrowing from us ($5000 USD) even though you may have $10,000 CAD available.
If you’re interested in borrowing the $5,000 USD so you can use $10,000 CAD available, you don’t have to place an exchange request just keep in mind that interest charges will apply to your account.