The ceremony will be held at Vidhan Bhawan premises at 4 PM, an official said.
Fadnavis had met BJP president Amit Shah in New Delhi on Tuesday and is believed to have got the nod for BJP probables in the expansion exercise.
Meanwhile, there is no clarity yet on the number of ministers to be inducted from Sena, with the figure varying from 7 to 12.
Presently there are eight cabinet and two ministers of state in the Fadnavis ministry sworn in on October 31.
However, a senior Sena leader told that the party will insist on one more minister to be inducted in Modi cabinet, besides Anant Gite.
"Our claim at the Centre remains. We hope something will emerge," the leader said.