As of 01/01/2021, the VoW service to validate UK (GB) VAT numbers ceased to exist while a new service to validate VAT numbers of businesses operating under the Protocol on Ireland and Northern Ireland appeared. These VAT numbers are starting with the “XI” prefix, which may be found in the “Member State / Northern Ireland” drop down under the new entry “XI-Northern Ireland”. Moreover, any quote of “Member State” is replaced by “Member State / Northern Ireland” and any quote of “MS” is replaced by “MS / XI”. All traders seeking to validate UK (GB) VAT numbers may address their request to the UK Tax Administration.
From the official Website:
GBis still in master andXIis missing