If I trade US stocks on Wealthsimple, are the funds held in US Dollars?

The U.S. stocks you invest in on WealthSimple are held in U.S. dollars.

When you are buying or selling American securities, there will be a prompt of how much it will cost from Canadian dollars to U.S. dollar, as well as the small exchange rate fee you will pay.

This is a lot better than some other investment platforms that do not share this information until after the transaction is executed.