Mind boggling amounts of ignorance on this thread. The question is not - which US brokers allow me to maintain accounts with canadian address. The question is - which US brokers allow me to maintain an account with canadian tax residency. Being specific helps resolve confusion.
It is not about mailing statements, it is about withholding taxes and tax reporting. Lol.
Fidelity allows accounts with CA tax residency but restricts some activities. If you want a fully functional brokerage which works across most country tax residencies, currencies, and accounts (401k, TFSA, RRP), go with IBKR and consolidate.