To dial out of South Africa, all you need to do is
1) dial the prefix + or 00,
2) followed by the destination country’s dialling code,
3) then the specific region code, minus the first zero of that code,
4) and, finally, the number wanted.

Example
If you wanted to call your sister currently living in London, you would dial + (prefix) 44 (the dialling code for the United Kingdom) 78 (the region code, minus the first 0) 123 4567 (the desired landline number).

Or

+44 78 123 4567

Calling a South African subscriber roaming abroad
You can either dial the number in local format (e.g. 083 123 1234) or in international format (e.g. +2783 123 1234).