The Blues will host Atletico Madrid at Kingsmeadow on Wednesday 3 March, with the first leg to kick-off at 7pm.
Chelsea will then travel to Italy for the second leg against the Spanish side the following week, with the game to take place on Wednesday 10 March.
Due to Spanish government restrictions on travellers entering the country from the UK due to the COVID-19 pandemic, it has been decided by UEFA and Atletico Madrid that the match will be staged in Monza, Italy
The fixture will be played at the Brianteo Stadium, Monza. The kick-off time will be confirmed in due course.