At 1129 GMT, the rand traded at 18.7925 against the dollar, about 0.88% stronger than its previous close.
The dollar last traded flat against major peers.
The rand jumped as much as 1% earlier in the day on the back of increased risk appetite as U.S. Treasury yields fell, Danny Greeff, co-head of Africa at ETM Analytics, told Reuters.
"For the (rand) bulls to remain in charge of the market in the coming days, U.S. Treasury yields would need to continue falling, or at least not rise further," Greeff added.
South Africa will host the leaders of Brazil, India and China for the Tuesday-to-Thursday summit, while Russian President Vladimir Putin will join virtually.
Putin is not travelling to South Africa because of an international arrest warrant for alleged war crimes in Ukraine.
The BRICS summit "is unlikely to provide the market with significant or sustainable momentum until the bloc adopts implementable policies," Greeff said.
Leaders will consider expanding membership of the BRICS grouping, as some members hope to position the bloc as a counterweight to the West.
On the Johannesburg Stock Exchange, the blue-chip Top-40 index was last trading around 0.6% higher from Monday's close.
South Africa's benchmark 2030 government bond was also firmer, with the yield down 5.5 basis points to 10.480%.
(Reporting by Tannur AndersEditing by Bhargav Acharya and Mark Potter)
