Finnish Business ID
A Finnish Business ID (Y-tunnus) is the identifier given to businesses and organisations by the Finnish Patent and Registration Office or Tax Administration through the Business Information System. It has seven digits, a hyphen, and a control mark. The ID identifies the entity, but it does not by itself show which tax or trade registers the business is currently entered in.
Why this matters when you invoice
The Business ID identifies the Finnish business or organisation named on an invoice and is useful for checking customer master data. It should not be treated as a summary of the organisation's current tax or e-invoice registrations.
Where it appears
The identifier is used across Finnish business administration and can be searched in the Business Information System. A recipient's e-invoice address and intermediary are separate routing fields.
Use Y-tunnus to find the entity, then check routing separately
A seller searches a customer's Y-tunnus, reviews the public company name and address, and adds those details to the invoice. If the customer wants a Finvoice or other e-invoice, the seller confirms the receiving address and intermediary separately.
Common mistakes
- Assuming the Business ID proves current VAT or tax registration.
- Using Y-tunnus as though it were the customer's e-invoice address.
- Skipping review of the public company name and address.
Search a Finnish company
Use Yrityshaku to review supported public company details before continuing to the invoice.
InvoiceCraftly's Finland company lookup shows supported public registry details; it does not determine tax registration, e-invoice address validity, or invoice compliance.
Official references
Sources and terminology reviewed 5 September 2026. Next evidence review: 4 December 2026.
Frequently asked questions
What does a Finnish Business ID look like?
It consists of seven digits, a hyphen and a control mark.
Does a Business ID show current tax registrations?
No. The identifier itself does not show which tax or trade registers the organisation is currently entered in.