When you invest with Wealthsimple, your assets are actually held by Canadian ShareOwner Investments Inc., Wealthsimple's custodial broker. In other words, ShareOwner executes trades and is where your securities are held. ShareOwner is regulated by IIROC and is a member of the Canadian Investor Protection Fund (CIPF), which is standard for brokerages in Canada. More on the CIPF here.
In the extremely unlikely event that Wealthsimple were to go out of business, your account would remain safe and be largely unaffected. All securities are registered in your name, and if we were to close, you could choose to keep your money with ShareOwner, or transfer it to a new advisor or your bank account.
Wealthsimple Inc. is a registered Portfolio Manager in Canada. Securities in your account may be protected up to $1,000,000 CDN through Canadian ShareOwner Investments Inc., if these brokerages were to go insolvent. See www.cipf.ca for more details.
Please note that your High-Interest Savings Account (HISA) is also insured, but is insured by the Canada Deposit Insurance Corporation (more on that here).