Looking for a company’s VAT number is possible by searching on online databases or by writing directly to the business. For privacy reasons, the UK government does not provide public directory for VAT numbers. If, however, you conduct business with a company, its VAT number should appear on invoices or other official documents. The European Commission’s VIES system may be used to verify VAT numbers for cross border transactions. Since the check a uk vat number is always confirmed before finalizing the transaction to maintain the tax compliance check as well as to avoid fraudulent transactions.