Continuous Net Settlement (CNS)

CNS refers to the NSCC’s automated book-entry accounting system, which centralizes the settlement of security transactions and maintains an orderly flow of security and money balances between participants. The CNS methodology serves to match transactions to securities available, resulting in one net receive or deliver position at the end of a given day.
How it Works                                                 
On T+2, all transactions for a given NSCC member are netted by issue to net long (buy) and net short (sell) positions, and then are further netted with positions that remained open after T+2 which includes positions due to settle that day as well as fail positions. If the net position is short (i.e. securities owed by the member to NSCC), the inventory in the member's DTC account is check for availability and if shares are available they are transferred from the member's DTC account to cover the short CNS obligation.  Net long positions (i.e. securities owed by NSCC to the member), are automatically credited to the member's DTC account. A daily money settlement is debited or credited to the member's account based upon the value of all settled trades plus or minus the mark-to-market figures on any open CNS positions.