It can take around 8 weeks for the CRA to send out a notice of assessment (NOA) for a return that has been filed by postal mail. Any tax payable is due on the filing deadline. After that they can charge you interest on unpaid amounts. So you can choose not to pay right away, but if you don’t get your NOA within the next few weeks, then you should pay the amount before or on the filing deadline to avoid penalties.
