The Spireites will travel to Stamford Bridge between Friday, January 7 and Monday, January 10.
Chelsea, managed by Thomas Tuchel, are currently third in the Premier League and have won the FA Cup a staggering eight times in their history.
Chelsea won the Champions League last season, beating Manchester City 1-0 in the final.
The tie will be very financially rewarding for Town no matter what the result is.
Winners of third round matches receive £84,000 in prize money.
Chesterfield’s National League match away at Stockport County will be postponed and rescheduled.
The Spireites have beaten Curzon Ashton, Southend United and Salford City to reach this stage of the competition for the first time since 2015.
Town beat League Two Salford 2-0 on Sunday with the goals coming from Liam Mandeville and Jim Kellermann.
The draw for the third round was made on Monday night.