Of equity transactions, 99.9% are sent as "locked-in" trades, which means that the marketplace has already compared them at the time of execution, confirming all details, including share quantity, price and security. NSCC sends to participants automated reports, which are legally binding documents that show trade details. These reports confirm that transactions have entered the clearance and settlement processing stream.

NSCC's guarantee of settlement generally begins midnight between T+1 and T+2. At this point, NSCC steps into the middle of a trade and assumes the role of central counterparty, taking on the buyer's credit risk and the seller's delivery risk. This guarantee eliminates uncertainty for market participants and inspires public confidence.

NSCC issues broker/dealers summaries of all compared trades, including information on the net positions of each security due or owed for settlement.

T+3 is settlement - the delivery of securities to net buyers and payments of money to net sellers. Broker / dealers instruct their settling banks to send or receive funds (through the Federal Reserve System) to / from DTC as NSCC's agent. Securities generally do not change hands physically. DTC transfers ownership between broker/dealers' accounts by book-entry electronic movements.