Gianluca Di Marzio reports that after negotiations during the day, the two clubs have agreed a deal for Zappacosta.
— Gianluca Di Marzio (@DiMarzio) September 17, 2020
The Italy international spent last season at Roma after barely featuring in the previous campaign with Chelsea.
However, a serious ACL injury meant the 28-year-old missed most of the season until the June restart.
Zappacosta will now join Genoa on a dry loan – meaning there is no agreed option to buy.
Chelsea paid €28m plus bonuses to sign Zappacosta from Torino in 2017.