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When are my Tax Payment and Filing payments processed to my TD Canada Trust account?

Payments must be made before midnight (local time) one business day before the due date. Payments entered on the due date will be late and may be subject to government penalties.
If your payment is due on a weekend or holiday, the payment due date is the next business date. The payment must be entered before midnight (local time) on the day before the due date.

For example: If the payment is due on the 15th and the 15th is a Saturday, then the system will change the due date to the 17th (next business day). The new due date is the 17th and you have until midnight (local time) on the 16th to enter the payment.