PyVAT with Checksums

A robust and accurate VAT number validation library for Python.

Why PyVAT with Checksums?

Most VAT validation libraries check if the string starts with the correct country code and has the correct length. That is not enough.

PyVAT with Checksums goes deeper to ensure data integrity:

• 🧮 Real Checksum Validation: We don't just count digits. We implement the official algorithms defined in the European Commission's VIES VAT Validation Routines specifications (Modulus 11, Modulus 97, etc.) to verify the number is genuinely valid.
• 🛡️ Stop Bad Data: Prevent typos and fake numbers from entering your system. A number can look right but be mathematically impossible—we catch that.
• ⚡ Zero External Dependencies: Lightweight and fast, perfect for high-throughput applications.

Features

• ✅ Mathematical Verification: Implements complex checksum algorithms for supported countries.
• 🌐 Multi-Country Support: Validates VAT numbers for all EU countries and many others (UK, Switzerland, Norway, Russia, etc.).
• 🔍 Format Checking: Validates structure, length, and allowed characters (numeric vs alphanumeric).
• 📦 Modern Python: Fully typed and compatible with modern Python versions.

Installation

pip install pyvat-with-checksums

Or using uv:

uv add pyvat-with-checksums

Usage

Import the validator and the countries you want to check against.

from pyvat_with_checksums import check_vat, belgium, austria

# 1. Valid VAT number (Belgium)
result = check_vat('BE0411905847', [belgium])
print(result.is_valid)
# Output: True
print(result.country.name)
# Output: 'Belgium'

# 2. Invalid Checksum (Looks like a valid format, but fails math check)
# This would pass a simple regex check, but fails here!
result = check_vat('BE0411905848', [belgium])
print(result.is_valid)
# Output: False

# 3. Check against multiple countries
result = check_vat('ATU12345678', [belgium, austria])
if result.is_valid:
    print(f"Valid VAT for {result.country.name}")

Supported Countries

Supports a wide range of countries, including but not limited to:

• 🇪🇺 European Union: Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden.
• 🌍 Non-EU: United Kingdom, Switzerland, Norway, Russia, Serbia, Brazil.

Development

To run tests locally:

make test

To run linting checks:

make lint