The UK Government Supplier Registration Service (SRS) is used by both buyers and suppliers to log in to procurement-related systems. The system assigns an identifier to each registered organisation, and may record details of other identifiers for the organisation, such as a DUNS number.
Crown Commercial Service (part of the Cabinet Office) publishes a list of the identifiers for all organisations that are registered in the system as **buyers**. Whilst primarily covering government agencies from all levels of government, the list also includes some private companies, trusts and charities who have been assigned the buyer role within the system.
The use of Supplier Registration System identifiers is considered a temporary measure. They should only be used when no other stable identifier for a government agency is available, and should not be used to identify private organisations, for which company registration numbers are preferred.