Your preliminary income assessment determines what you are paid each month. It tells you your withholding rate and your total deductions and allowances.
When you change your preliminary income assessment, you also change your tax card, which will automatically be sent to your employer or other parties, such as your pension provider.
In November, you receive your preliminary income assessment from the Danish Tax Agency (Skattestyrelsen) which applies to the next year. It is based on the information that the Tax Agency has from previous years. It is a good idea to check to see if the figures are correct.
It is also a good idea to change your preliminary income assessment if your financial circumstances change to ensure that you pay the right amount of tax each month.