Toll tariffs on national roads will increase by 6.017% on Saturday, the South African National Roads Agency Limited (Sanral) said.

"We use the inflation rate as a guide, as we do not want to increase road usage costs beyond what is reasonable," Sanral CEO Nazir Alli said in a statement on Monday.

Tariff adjustments would be made on the N3 toll road between Johannesburg and Durban, the N4 highway between the Mozambican border and the Botswana border, as well as on toll road sections of the N1, N2, N17, and R30, he said.

These adjustments were in line with the Consumer Price Index (CPI). They had been approved by Transport Minister Dipuo Peters and then gazetted, Alli said.

Gauteng Freeway Improvement Project (GFIP) tariffs would not be adjusted for the second year running.