The securities settlement system (NBB-SSS)

The National Bank administers a settlement system for securities (formerly called Clearing), which ensures the secure handling of transactions in, predominantly, dematerialised securities (securities that only exist in the form of an entry on an account).


This system enables the processing of transactions on both the primary market (on which new securities are issued) and the secondary market (on which financial instruments already in circulation are exchanged). The total outstanding amount held on account is comprised mainly of securities issued by the Belgian Government, such as treasury certificates (short-term securities), linear bonds  (OLOs) and strips. It also comprises short and long-term securities issued by other government bodies or by the private sector.

How the system works

The system ensures the settlement of transactions based on instructions sent by the two counterparties (dual notification principle). It also ensures that delivery of and payment for the securities are effected simultaneously and irreversibly (delivery against payment principle). The system settles transactions on gross basis. The system also takes care of the collection and refunding of taxes on the securities (X/N system), both at the time of settlement of a transaction and when the proceeds are paid.

The participants can follow their instructions and their positions by means of Ramses.

System Working days

In principle, the settlement system shall operate daily troughout the year except on Saturdays, Sundays and the other days on which the TARGET system is closed.    

An integrated system within TARGET2

The NBB-SSS operates as an "integrated system" within Target2 via the interface prescribed for outside systems (ASI = Ancillary System Interface).

This means that both the cash side and the security side of "delivery versus payment" transactions are settled in full on the SSS platform. Thus, in order to ensure that the system works normally, the participants have to transfer cash from their TARGET2 account to their cash account in the securities settlement system (and vice versa). Market participants who are not direct participants in TARGET2 have to appoint an intermediairy (Settlement Bank Agent) in order to fund this account. The cash funds held in this account will also be used for settling DVP transactions as well as for the payment of corporate actions.


1 TARGET2 - SECURITIES - Adaptation plan

2 Management Committee

3 User Committee



Rule Book 



Various lists

Other documents