The deal was concluded through SEACOM South Africa.
"FibreCo owns and operates a national open access dark fibre network, providing infrastructure, connectivity, and services across South Africa. The acquisition is subject to approval by the South African Competition Commission," said SEACOM.
The company said that this marks another step towards its goal of expanding its African footprint.
FibreCo's network also connects the SEACOM subsea cable system to the WACS cable, it added.
"The FibreCo acquisition significantly strengthens SEACOM's operations in South Africa by creating a platform for the expansion of its business services."