Microsoft Dynamics 365 Business Central can validate the format of VAT registration numbers when you enter them on customer and vendor cards. The validation checks that the number matches the format defined for the customer’s country or region.
You control the validation in the Country/Region table. Each country can have one or more VAT registration number formats defined under Navigate, VAT Reg. No. Formats.
For Denmark, the valid formats are DK followed by eight digits, or just eight digits, with the option to enter them in pairs of two.
If you delete the format for a country, Business Central stops validating VAT registration numbers entered for customers in that country.
How VAT registration number validation works in Business Central
When you type a VAT number into the VAT Registration No. field on a customer card, Business Central checks the format against the rules set up for that customer’s country. If the number does not match, you get a validation error telling you the entry does not meet the country’s requirements.
This is a practical safeguard against typos and incorrectly formatted numbers. If you enter a Danish VAT number that does not follow the Danish format, the system flags it right away instead of letting an invalid number slip into your data.
Where to find the VAT registration number formats
The formats are defined per country in the Country/Region table. To check or adjust them:
- Open the Country/Region table and find the relevant country, for example Denmark.
- From the top menu, go to Navigate, then Country/Region, and open VAT Reg. No. Formats.
- Here you can see the allowed formats for that country.
For Denmark you will find two valid options: DK followed by eight digits, or eight digits on their own. Both can be entered in pairs of two.
What happens if you remove the format
If you delete the format entry for a country, Business Central no longer runs any validation on VAT registration numbers for customers in that country. You can then type anything into the field without the system checking it.
That can be useful if you handle countries with formats the standard setup does not cover, but keep in mind you lose the protection against incorrect entries. In most cases it is better to keep the format in place so the validation does its job.
Q&A
What is the valid VAT registration number format for Denmark in Business Central?
The valid formats are DK followed by eight digits, or eight digits on their own. Both can be entered in pairs of two.
Where do I set up VAT registration number formats in Business Central?
Open the Country/Region table, find the relevant country, and go to Navigate, Country/Region, VAT Reg. No. Formats. Each country can have one or more formats defined here.
Why does Business Central reject the VAT number I enter on a customer card?
Business Central validates the VAT number against the format defined for the customer’s country. If the number does not match that format, you get a validation error stating the entry does not meet the country’s requirements.
How do I turn off VAT registration number validation for a country?
Delete the format entry for that country in the VAT Reg. No. Formats table. Business Central will then stop validating VAT registration numbers entered for customers in that country.