Dlamini was the most common surname among babies born and registered in all three years - 2016, 2015 and 2014.
The next most common surnames were Nkosi and Ndlovu.
A total of 969,415 births was registered in 2016. In almost two-thirds of instances, 62%, the father was not named when the birth was registered.
StatsSA said: "This finding is consistent with that of previous years."
Most mothers were 20 to 29 years old.
More than 10% fewer babies were registered last year compared to 2015.
Most babies were registered in Gauteng (235,218), KwaZulu-Natal (198,628) and Limpopo (122,890).
March and September were the busiest months, with 9% and 8.6% of births. - TimesLIVE