what has been the history of u s stock settlement cycles 
a century ago stocks were settled t 1 but by hand as interest in stock trading and volume of shares increased sharply so too did the need to streamline the settlement process the sec originally established a standard settlement cycle of five business days or t 5 for most securities transactions in order to provide sufficient time for the physical delivery of stock certificates and the corresponding payments 5 this was changed to t 3 in 1993 shortening the prevailing practice at the time of settling securities transactions within five business days of trade date in 2017 the sec shortened the standard settlement cycle from t 3 to t 2 and in 2024 from t 2 to t 1 3