Slovenia VAT API — Validate Slovenia VAT Numbers in Real Time
REST JSON endpoint for verifying Davek na dodano vrednost (DDV) numbers against the official EU VIES register, with national registry fallback where available and a VIES consultation number on every successful check.
Why a Slovenia-aware VAT API
In Slovenia, VAT is known as Davek na dodano vrednost (DDV) and the current standard rate is 22%. Every Slovenia VAT number starts with the prefix SI and follows a fixed structure issued by the Slovenia tax authority. A generic VAT validator that ignores country-specific quirks will accept malformed input, miss the country's format rules, and fail to surface the local registry identifier that accountants and auditors actually need.
The vatnode API normalises DDV input, runs the official VIES check, falls back to the Slovenia national company registry when VIES is unavailable, and returns a single JSON shape with the consultation number, company data where published, and the current Slovenia VAT rates inline.
Slovenia VAT number format
SI + 8 digits^SI\d{8}$Real Slovenia VAT numbers you can validate right now:
- SI82646716 — Krka d.d., Novo Mesto
- SI91132550 — NLB d.d.
- SI98511734 — Telekom Slovenije d.d.
Validating Slovenia VAT numbers — code examples
All three examples validate the same Slovenia VAT number SI82646716.
curl https://api.vatnode.dev/v1/vat/SI82646716 \
-H "Authorization: Bearer YOUR_API_KEY"const res = await fetch(
'https://api.vatnode.dev/v1/vat/SI82646716',
{ headers: { Authorization: `Bearer ${process.env.VATNODE_API_KEY}` } }
)
const data = await res.json()
console.log(data.valid, data.companyName, data.consultationNumber)import os, httpx
r = httpx.get(
"https://api.vatnode.dev/v1/vat/SI82646716",
headers={"Authorization": f"Bearer {os.environ['VATNODE_API_KEY']}"},
)
data = r.json()
print(data["valid"], data["companyName"], data["consultationNumber"])What you get back
A successful response for a valid Slovenia VAT number looks like this:
{
"valid": true,
"vatId": "SI82646716",
"countryCode": "SI",
"countryName": "Slovenia",
"companyName": "Krka d.d., Novo Mesto",
"consultationNumber": "WAPIAAAAXk7ZpY3o",
"source": "VIES",
"countryVat": {
"currency": "EUR",
"standardRate": 22,
"reducedRates": [5,9.5],
"superReducedRate": null,
"parkingRate": null
},
"verifiedAt": "2026-05-19T08:14:22Z"
}When the number is not registered, valid is false and company fields are null. The consultationNumber is the EU VIES requestIdentifier — the documented audit reference for reverse-charge "reasonable care" evidence.
Slovenia VAT rates
vatnode returns the current Slovenia DDV rates inline with every successful response. Today's rates (standard 22%, reduced 5%, 9.5%) are sourced from the European Commission TEDB feed and refreshed daily.
| Rate type | Value |
|---|---|
| Standard | 22% |
| Reduced (1) | 5% |
| Reduced (2) | 9.5% |
VIES vs national fallback for Slovenia
VIES is the primary data source for Slovenia validation — it is the authoritative EU register and the only source that produces a consultation number. When VIES returns a transient error (timeout, MS_UNAVAILABLE, SERVICE_UNAVAILABLE), vatnode automatically queries the Slovenia national company registry as a fallback so your checkout or invoicing pipeline keeps working.
The response includes a source field that tells you which system answered — VIES for the EU register, or the Slovenia national-registry source code when the fallback ran.
Slovenia is one of the EU countries where vatnode keeps validating during EU VIES outages via a direct national registry adapter. See coverage matrix for the full list.
Slovenia VAT API — FAQ
Is the Slovenia VAT number the same as the company registration number?
No. The Slovenia DDV number is issued by the tax authority for VAT purposes; the national registry identifier is a separate ID issued by the company registry. vatnode returns both fields (registryCode + registryCodeName) for Slovenia when the data is available.
How fast is Slovenia VAT validation through vatnode?
Cached responses return in single-digit milliseconds. Live VIES lookups for Slovenia typically complete in under one second; a 15-minute Redis cache is applied to identical VAT IDs.
Does the API work for Slovenia sole traders and small businesses?
Yes. If a Slovenia sole trader or small business is registered for DDV and listed in VIES, vatnode validates the number and returns the same response shape as for corporate entities. The valid field is true regardless of legal form.
What happens if EU VIES is down for Slovenia?
vatnode falls back to the Slovenia national registry adapter when VIES returns a transient error (timeout, MS_UNAVAILABLE). Validation keeps working from the national source; the response includes a source field so you can tell which system answered.
What is the consultation number returned for Slovenia checks?
The consultationNumber is the VIES requestIdentifier — a unique reference issued by the EU VIES service that proves the check was performed against the official EU register on a specific date. It is the EU's documented mechanism for "reasonable care" evidence under the reverse-charge rules and is returned on every successful VIES validation, including Slovenia.
See also
Start validating Slovenia VAT numbers
100 validations per month on the free plan, no credit card required. REST JSON over HTTPS, VIES consultation number on every check, Slovenia national registry fallback, EU-hosted by default.