UK VAT Validation
The UK left the EU VAT system on 1 January, 2021, separating UK VAT numbers from EU VAT numbering and from validation through the VAT Information Exchange System (VIES). Because of this, the UK has released its own online service for UK VAT number validation.
February 5th, 2021's patch to WHMCS 7.10 and later updates our VAT tax support to use the new HMRC system for your customers' UK VAT numbers. EU VAT numbers will continue to be validated through VIES.
To continue successfully validating UK VAT numbers, you must update your information in WHMCS.
To continue UK VAT validation, you must update the VAT Settings tab at Configuration > System Settings > Tax Configuration.