All administration and collection of taxes, VAT, customs etc. in Denmark is placed with one authority called Skat (Tax).
Skat is the generic term for one main tax centre and 30 local tax centres. You can find the relevant addresses and telephone numbers of the tax centres
here, under the menu item "kontakt". Skat has one telephone number that is the contact number for all the tax centres; 72 22 18 18.
The tax centres assist and advise citizens and businesses residing in the area and check that citizens and businesses comply with applicable rules. The tax centres will provide answers to any question you may have with regard to your income tax return and other taxrelated matters.
Businesses can get assistance with accounts, payroll accounting for employees of the enterprise, VAT, excise duties, corporation tax, customs duty etc.
The tax centres handle all aspects of your tax affairs. As Skat is one large nationwide authority, you can apply in person at any tax centre in the country.
In tax questions, always apply directly at Skat, not at the local authority.
By the way, in Denmark license plates for motor vehicles are administered and distributed by Skat.