The interest on a 3a account is higher than on a normal savings account. Therefore, if possible, you should pay into the 3a account at the beginning of the year in order to receive interest for the whole year.
The Pillar 3a account is a frozen account. The saved assets can be withdrawn earliest five years before ordinary retirement age. Exceptions that make advance withdrawal possible are, for example, purchase of property or the step into occupational self-employment (also see advance withdrawal ).