 The Second Avenue Subway ( officially the IND Second Avenue Line ; abbreviated to SAS ) is a future New York City Subway line that has been under discussion for almost a century . The line will run primarily under Second Avenue on the East Side of Manhattan . A first phase of this new line is expected to open on December 30 , 2016 , having been under construction since 2007 . It will run between 96th Street and Second Avenue and the existing 63rd Street Lines , where it will connect to the BMT Broadway Line and the rest of the subway system . The Q train will provide full @-@ time service on phase one and will serve about 200 @,@ 000 daily riders . The full line , when funded , will be built in three additional phases , allowing portions of the line to open before the entire line is completed . When complete , it will be served by a proposed T train and is projected to serve about 560 @,@ 000 daily riders . The full proposed Second Avenue line would consist of 16 stations and 8 @.@ 5 miles ( 13 @.@ 7 km ) of tunnel , and is expected to cost over $ 17 billion . 
