Tax returns and assessments
All resident taxpayers must file an annual income tax return, unless their only
income is employment income from a single employer. Even in this case, it may
be to a taxpayer’s advantage to file a return if, for example, the income has
fluctuated from month to month and the employer has not made compensating
adjustments to the monthly “wage” withholding tax calculations.
The tax year is the calendar year and the return is, in principle, due by the
following May 31 or, if a tax consultant has been appointed, by December 31.
The May deadline can, however, be extended and an informal application is
often sufficient. The December deadline can be extended for a further two
months, but only for a specific reason.