Thomas, who won the 2018 Tour de France, pulled out of the Giro in 2020 after suffering a hip fracture in a crash. Three years earlier his race came to an end after he damaged his shoulder in a pile-up involving a police motorbike.
The 2023 Giro will be held from May 6th-28th.
INEOS Grenadiers rider Thomas finished third in the Tour de France this year.