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Getting your BTW-id (VAT number)

How to get your Dutch VAT number after registering with the KVK, what your BTW-id is used for, and the difference between your BTW-id and omzetbelastingnummer.

ZZP Belasting 15 June 2026 5 min read

When you register as a freelancer with the Dutch KVK (Chamber of Commerce), you automatically get two numbers: a BTW-id (VAT number) and an omzetbelastingnummer (sales tax number). They sound similar, they're related, but they're not the same, and knowing which one to use — and when — matters. This guide walks you through what they are, why there are two, and how to use them correctly.

What happens after KVK registration

The moment your KVK registration is processed (usually within a day or two), the Belastingdienst automatically assigns both numbers:

  1. BTW-id (BTW-identificatienummer): Your VAT identification number, used for cross-border VAT and EU reporting.
  2. Omzetbelastingnummer (sales tax number): Your national sales tax number, used for domestic VAT returns in the Netherlands.

You don't have to request these; they're automatically generated. You'll receive notification of both numbers by post, typically within two weeks of your KVK registration.

Why two numbers? Privacy

The two-number system is deliberate. Your omzetbelastingnummer is needed for your domestic tax dealings with the Belastingdienst, while your BTW-id is a public-facing number you publish on invoices and share across borders (EU trade). This split reduces privacy risk: your internal number stays with the tax office, your BTW-id goes on public documents.

The BTW-id: what it looks like and where it appears

Your BTW-id has a standard EU format:

NL [8-digit number] B [2 digits]

For example: NL123456789B01 (not a real number, just the format).

This number appears on:

  • Your invoices (required by law for VAT purposes).
  • Your website (if you do cross-border trade).
  • EU declarations like the ICP (Intra-Community Supplies).
  • Export paperwork and reverse-charge invoices.
  • B2B quotes and contracts (professional practice).

It's your public VAT identity. Customers, especially in other EU countries, use it to verify that you're a legitimate, VAT-registered business.

The omzetbelastingnummer: what it's for

Your omzetbelastingnummer is a slightly different format:

[8 digits] [1 letter] [2 digits]

For example: 12345678C01 (not real, just showing the format).

This number is for:

  • Your domestic VAT returns (quarterly forms filed with the Belastingdienst).
  • Your tax identification within the Netherlands.
  • Your correspondence with the Dutch tax authority.
  • Your business bank account (some banks ask for it during onboarding).

You'll likely use it less often than your BTW-id, unless you're constantly filing VAT returns and corresponding with the Belastingdienst in person.

Two numbers, one business

NL123456789B01
BTW-id (public, on invoices)
12345678C01
Omzetbelastingnummer (domestic, tax office)
~2 weeks
Time to receive both by post

When to use which number

Use your BTW-id:

  • On every invoice (mandatory for VAT purposes).
  • When trading with EU businesses (they'll ask for it to verify your registration).
  • On ICP declarations and export documents.
  • On your website (if you advertise cross-border services).
  • In any correspondence that's public-facing or shared outside the Netherlands.

Use your omzetbelastingnummer:

  • On your VAT returns (filed via Mijn Belastingdienst).
  • In correspondence directly with the Belastingdienst.
  • For internal Dutch tax administration.
  • When a Dutch bank or supplier specifically asks for your "Dutch tax number."

Don't confuse them: If you accidentally put your omzetbelastingnummer on an invoice instead of your BTW-id, it's not a disaster, but it's non-standard and may confuse your customer (especially abroad). If you're using invoicing software, ensure it pulls the right number — usually BTW-id by default.

Your invoicing software should have both

Most modern bookkeeping tools store both numbers. When you set up your business profile, enter both and let the software automatically populate the BTW-id on invoices (it should do this by default) and use the omzetbelastingnummer for your tax return fields.

What if you don't receive your numbers by post?

If more than three weeks have passed since your KVK registration and you haven't received your numbers:

  1. Log in to Mijn Belastingdienst (the Dutch tax authority's portal, accessed via DigiD).
  2. Look for "BTW-identificatie" or "Omzetbelasting" in your business profile. Your numbers should be visible there.
  3. If they're not visible yet, contact the Belastingdienst directly (via the portal's contact form or by phone).

Your numbers are assigned instantly on the back end; postal delays can happen. The online account is the source of truth if mail is slow.

Verification: checking a customer's VAT number

When you're invoicing an EU customer and want to verify their VAT registration, you can use the VIES tool (VAT Information Exchange System) at https://ec.europa.eu/taxation_customs/vies/.

This works for other EU countries' VAT numbers. For Dutch numbers, you can also check at belastingdienst.nl if needed.

Frequently asked questions

Do I have to print both numbers on my invoices?
No. Print your BTW-id on invoices (it's required for VAT purposes). The omzetbelastingnummer is for your internal Dutch tax dealings, not for external invoices.
If I'm on the KOR (small business exemption), do I get a BTW-id?
Yes. Even KOR-exempt businesses are assigned a BTW-id after KVK registration. You just don't charge VAT or file VAT returns. The number is there for future reference if you ever exit the exemption.
Can I change my BTW-id or omzetbelastingnummer?
No. These are permanent identifiers tied to your KVK registration. If you need a new one, you'd have to re-register, which is not practical. If there's an error in your registration, contact the Belastingdienst to correct it.
What if I lose the letter with my numbers?
Log into Mijn Belastingdienst with your DigiD. Both numbers are displayed in your business profile. You can screenshot or print them for your records.

Getting your BTW-id is automatic and hassle-free — it's one of the few things the Dutch bureaucracy does smoothly. Once it arrives, store it safely (it's on your official documents anyway), and make sure it's entered correctly in your invoicing software. It's the primary number your customers see and use, so accuracy matters. ZZP Belasting stores both your numbers and auto-fills the right one on every invoice, so you're always compliant and your customers always see the correct public identity.

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