The Border Management Authority (BMA) says it has processed 1 596 Malawian and Zimbabwean nationals during a 13-hour operation at the Beitbridge Port of Entry.
This includes 17 buses carrying 1 129 Malawian nationals who were found without valid documentation authorising their stay in South Africa.
An additional 467 Zimbabwean nationals were also processed for deportation.
Officials say all travellers were handled in line with immigration laws.
More buses carrying Malawian nationals are expected to arrive later tonight or during the early hours of Friday morning as repatriations continue.
BMA Commissioner Dr Michael Masiapato praised teams from Home Affairs and the South African Police Service for their endurance and commitment during the operation.
Meanwhile, the inter-ministerial committee on migration says it has developed an implementation plan to strengthen migration management.