Capitec Bank added 1.3 million customers during in the period between 1 March 2016 and 28 February 2017.
On Friday (26 May) the Stellenbosch based bank had 8.9 million clients, about 11% of the market.
Capitec Bank has the best digital offering (including mobile) in South Africa, according to a survey conducted by Modern Independent Insights Agency.
It has the lowest bank charges in South Africa, according to the 2016 Solidarity Bank Charges Report.
It is the best bank in the world, according to international banking advisory group Lafferty.