The club have agreed personal terms with the player and he is set to have a medical before the transfer is completed.
Football fans will recall that Chelsea have been hunting for a replacement for Antonio Rudiger who left for Real Madrid, since the days of Thomas Tuchel.
RB Leipzig’s 20-year-old Croatian international defender Josko Gvardiol had been a target but the Londoners could not agree terms with the Bundesliga side.
Other players under consideration include Eintracht Frankfurt’s 23-year-old Evan N’Dicka and Bayer Leverkusen’s 20-year-old Piero Hincapie.
The departure of Andreas Christensen and Marco Alonso to Barcelona only intensified Chelsea’s search.
Also, Thiago Silva is unlikely to stay at Stamford Bridge beyond the end of the season, given he is 38.
Hence, beefing up the defence is a priority.
It’s for this reason that Kalidou Koulibaly, Wesley Fofana and Marc Cucurella were all brought in last summer.
Benoit has 135 appearances for Monaco after breaking into the first team five years ago.
He has also, two caps for the French national team so far.
Chelsea are also believed to be in talks with Benfica’s midfielder Enzo Fernandez, 21, who has a £106m release clause.
Chelsea could also turn to the more affordable Argentine international Alexis Mac Allister at Brighton, though he also has a long-term contract on the south coast.
They may also attempt to bring in Joao Felix from Atletico Madrid on loan after he has failed to command a regular place this season under manager Diego Simeone.