BTW-id vs omzetbelastingnummer: which Dutch VAT number goes on your invoice

A Dutch business has two VAT numbers. The VAT ID (btw-identificatienummer, btw-id) goes on your invoices, your website and your emails; the VAT tax number (omzetbelastingnummer) is only for contact with the Belastingdienst, such as your VAT return and its payment.

Side by side

	VAT ID (btw-id)	VAT tax number (omzetbelastingnummer)
Where you use it	invoices, website, quotes, EU clients	VAT return, letters from the Belastingdienst
Public	yes, clients check it in VIES	no
Under the KOR	not needed on your invoices	still used for the Belastingdienst

Both start with NL and look alike, which is why they get mixed up.

Worked example

Tom invoices a GmbH in Berlin. His invoice shows his VAT ID, the client’s German VAT number and the reverse-charge line. The client checks Tom’s VAT ID in VIES. When Tom files the quarter’s return in Mijn Belastingdienst, it is filed under his VAT tax number, which no client ever sees.

More on EU clients in Invoicing foreign clients from the Netherlands.