According to the Independent Examinations Board chief executive Anne Oberholzer, the pass rate was an increase from 98.76 percent in the previous year.
There were 11,514 full-time pupils and 858 part-time students who sat for examinations in October and November 2018. These are students who attend privately-run schools in the country.
Oberholzer said 90.65 percent had qualified for entry to study for a degree, up from 88.5 percent the previous year.
The high pass rate could be attributed to the removal of the list of designated subjects, she added.
Previously, students had to get 50 percent or more in a minimum of four designated subjects. In 2018, this was changed and pupils could obtain 50 percent in any four or more subjects, except for Life Orientation course, she said.
“Umalusi (the official exams regulatory body) has monitored all aspects of the 2018 examination process and has declared the results to be fair and valid,” Oberholzer said.