One way to ensure that no interest will be assessed for late instalments is:

A To pay the averateof the three amounts calculated using the 3 alternative calculations on or before the required date.

B To pay the estimated tax owing for the current year on the first instalmentdue date.

C To pay the lowest amount calculated using the 3alternative calculations on or before the required dates.

D To pay the amounts provided by the CRA in their instalmentreminder on or before the required dates.