As of 2013, the MTA has spent nearly $2 billion to procure a replacement for the M3 series, the M9. The fleet is similar to the M7, and the first cars arrived in 2018. , there were 92 M9 cars planned, with options for up to 494 more. However, due to delays in the M9 contract, the Long Island Railroad plans to rebuild, and keep at least 80 to 100 M3 cars in service through at least 2024. Metro-North also planned to overhaul their M3A units, but later stated that they "are working with LIRR to procure new M9A cars in the next Capital Program to provide additional capacity and to replace their existing M3s instead of overhauling same."