EU VAT Validation for US SaaS Companies

By Remco from Avatcado

A US SaaS supplier can fall within the EU reverse charge rules. For ordinary B2B services taxable where the EU business customer is established, Article 196 makes the customer account for VAT when the supplier is not established in that Member State. The supplier invoices without charging VAT. VAT validation helps you collect registration evidence for this assessment.

Business status and VAT registration

A valid VAT number is evidence of registration. It does not by itself establish that the customer is buying as a business, which establishment receives the service, or that reverse charge applies. Equally, a missing or invalid number does not independently prove that the customer is a consumer. Article 18 of Implementing Regulation 282/2011 includes an evidence route for customers awaiting a VAT number they have applied for.

Collect business details, validate the VAT number when supplied, and resolve contradictory or missing evidence. The reverse charge guide sets out the conditions and links to the Commission and legislation. Specialist services and other exceptions are outside this ordinary SaaS flow.

B2B and consumer sales

  • Qualifying B2B services: the EU customer accounts for VAT under reverse charge. This is different from a statutory zero rate.
  • Digital services to EU consumers: customer-location VAT generally applies. A US supplier with no EU establishment can use the optional non-Union OSS to report eligible services through one registration instead of separate registrations.

The EUR 10,000 cross-border threshold is not available to a US supplier with no EU establishment. A validation timeout must not silently move a customer into the consumer path. See the OSS and IOSS guide for the difference between scheme identifiers and ordinary VAT numbers.

How to validate EU VAT numbers from the US

VIES is publicly accessible from the US. Avatcado exposes it through a REST API with structured results and errors. Use the runnable registration-evidence example on your backend. Pass the customer's number; the requester number is optional.

Preserve Verified, Invalid, Unavailable and Error as separate outcomes. Only an explicit live, noncached VIES result establishes a fresh valid or invalid check in that example. Save the timestamp, source and request ID, and any consultation number actually returned. No EU VAT registration is needed to use Avatcado.

Do US companies need an EU VAT number?

Supplying only the ordinary B2B services described here, with the EU customer liable under reverse charge, generally does not require an EU VAT registration solely for those supplies. Consumer sales, an EU establishment, goods or specialist transactions can change the position.

Do not obtain or invent a requester VAT number just to fill an API field. If you have a genuine suitable VAT registration, you can supply it when requesting consultation evidence. A non-Union OSS identifier is not a VIES requester number, and a consultation number is not guaranteed even when a requester is supplied.

What about the UK, Switzerland, Norway, and Australia?

These jurisdictions have their own VAT or GST rules. GB numbers validate via HMRC; XI numbers remain in VIES for Northern Ireland goods arrangements. Avatcado also supports Swiss, Liechtenstein, Norwegian and Australian registration checks. A successful check in those registries does not determine EU or local tax treatment.

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Read the API documentation or the TypeScript integration guide for integration details.

Frequently asked questions

Do US companies need to charge EU VAT?

For ordinary B2B SaaS taxable at an EU customer establishment, Article 196 makes the customer liable when the US supplier is not established in that Member State. The supplier invoices without charging VAT. Consumer digital services generally follow customer-location VAT; a non-EU supplier can use the optional non-Union OSS for eligible sales. VAT validation supplies registration evidence but does not settle customer status, establishment or tax treatment on its own.

Can I access VIES from the US?

Yes. VIES is publicly accessible from the US, and Avatcado also accepts checks from a US backend. No EU VAT registration is needed to use Avatcado. Supply the customer VAT number and optionally your genuine suitable requester VAT number. If you have none, omit it. Retain any consultation number actually returned, and explicitly record missing proof.

What if my EU customer doesn't have a VAT number?

Resolve the customer evidence rather than automatically classifying the sale as B2C. Article 18 of Implementing Regulation 282/2011 includes an evidence route when a customer has applied for a VAT number but has not received it. The customer capacity and receiving establishment also matter. For a confirmed consumer digital-service sale, customer-location VAT generally applies; a US supplier with no EU establishment cannot use the EUR 10,000 cross-border threshold.

Do I need a separate integration for UK customers?

Avatcado uses the same endpoint for GB numbers through HMRC and EU numbers through VIES. XI numbers remain in VIES for Northern Ireland goods arrangements. Swiss, Liechtenstein, Norwegian and Australian checks are also supported. Those registry checks do not determine the relevant country tax treatment; the fresh VIES evidence example is specifically scoped to EU registration evidence.

Sources

Try it on a real VAT number

Check any VAT or GST number against the official registry for free, no account needed.

Related guides

EU VAT Reverse Charge: What Developers Need to Know

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