Home / Validate VAT / Slovenia
Validate Slovenia VAT Numbers via API
When building B2B applications that serve Slovenia (Slovenija), validating your customers' DDV ID (Davek na dodano vrednost Identifikacijska številka) is essential for EU VAT compliance and protecting your business from tax liability.
The TaxID API provides instant validation of Slovenia VAT numbers through the EU VIES (VAT Information Exchange System). Every request returns the registration status, company name, and registered address — with sub-100ms response times for cached results.Slovenia applies a standard VAT rate of 22% (DDV ID) and is fully supported by the VIES system.
QUICK START
curl -H "Authorization: Bearer YOUR_API_KEY" \ http://localhost:3000/api/v1/validate/SI/SI12345678
Code examples
Choose your language. Every example validates a Slovenia VAT number and returns the registration status with company details.
const res = await fetch('http://localhost:3000/api/v1/validate/SI/SI12345678', {
headers: { 'Authorization': 'Bearer YOUR_API_KEY' }
});
const data = await res.json();
// { valid: true, status: "active", company_name: "...", country_code: "SI", cached: false }
console.log(data);When to validate Slovenia VAT numbers
B2B cross-border sales
When selling goods or services to Slovenia businesses in other EU member states, you must verify their DDV ID (Davek na dodano vrednost Identifikacijska številka) to correctly apply zero-rate VAT under the reverse charge mechanism. Failing to validate before zero-rating a transaction makes your company liable for the full VAT amount if the customer turns out to be unregistered.
E-commerce and SaaS checkout
If your platform accepts Slovenia business customers, validating the DDV ID (Davek na dodano vrednost Identifikacijska številka) at checkout determines whether to apply 22% VAT (B2C) or zero-rate the sale (B2B reverse charge). This directly affects your invoicing, revenue recognition, and quarterly VAT return figures.
Supplier and partner onboarding
For ERP systems, procurement platforms, and DAC7-regulated marketplaces, validating aSlovenia supplier's DDV ID (Davek na dodano vrednost Identifikacijska številka) during onboarding prevents invalid numbers from entering your accounting system — which can cause rejected invoices and audit failures. Validate once at onboarding, then periodically re-validate to catch deregistrations.
About Slovenia VAT format (DDV ID)
Slovenia is a small but strategically positioned EU market between Italy and Austria. The DDV ID (VAT ID) is 8 digits. Slovenia increased its standard VAT rate from 22% to 22% in recent years, maintaining one of the more moderate rates in the region.
| Field | Value |
|---|---|
| Country code | SI |
| Local name | DDV ID (Davek na dodano vrednost Identifikacijska številka) |
| Format | SI + 8 digits |
| Regex pattern | ^SI[0-9]{8}$ |
| Example | SI12345678 |
| VIES supported | Yes |
VAT rates in Slovenia
Slovenia applies a standard DDV ID rate of 22%. Reduced rates of 9.5% and 5% apply to essential goods and services.
| Rate type | Percentage | Currency |
|---|---|---|
| Standard rate | 22% | EUR |
| Reduced rate | 9.5% | EUR |
| Reduced rate | 5% | EUR |
Frequently asked questions
What is the Slovenia VAT number format?
Slovenia VAT numbers (DDV ID (Davek na dodano vrednost Identifikacijska številka)) follow the format: SI + 8 digits. A valid example is SI12345678. The TaxID API validates both the format locally and the registration status via VIES, ensuring you only accept properly registered EU businesses.
Is VAT validation mandatory for selling to Slovenia businesses?
EU VAT law requires that suppliers verify a customer's VAT registration before applying zero-rate treatment to intra-community B2B supplies. If you sell goods or services to a Slovenia business without VAT and their registration is invalid, your company may be liable for the full VAT amount plus interest and penalties. Validation is not just recommended — it is your legal due diligence obligation.
What is the standard VAT rate in Slovenia?
The standard VAT rate in Slovenia is 22% (DDV ID). Reduced rates of 9.5% and 5% apply to certain goods and services such as food, books, and medical supplies. The TaxID API's /rates endpoint returns all current rates for programmatic access.
How long does Slovenia VAT validation take with TaxID?
For cached results (previously validated in the last 24 hours), the TaxID API responds in under 10ms. For uncached requests, the VIES SOAP call to the Slovenia tax authority typically completes in 100–400ms. Active (valid) numbers are cached for 24 hours; invalid numbers are cached for 1 hour to balance performance with freshness.
Does the TaxID API support VIES for Slovenia?
Yes. Slovenia is fully supported by the EU VIES system and the TaxID API. VIES validates Slovenia VAT numbers in real time against the Slovenia national tax authority's registration database. Slovenia is a small but strategically positioned EU market between Italy and Austria. The DDV ID (VAT ID) is 8 digits. Slovenia increased its standard VAT rate from 22% to 22% in recent years, maintaining one of the more moderate rates in the region.
Start validating Slovenia VAT numbers
Free plan includes 100 validations/month. No credit card required.
Get free API keyAlso validate VAT in: