Banks:
The usual opening hours for banks in South Africa are:
Monday to Friday 9AM-3.30PM Saturday 9AM-11AM

The biggest banks in South Africa are:
ABSA
FNB (First National Bank)
Nedbank
Standard Bank
Wesbank
NBS

Post:
The usual opening hours are:

Monday to Friday
8AM-4.30PM

Saturday
8AM-12PM

Shops and Malls:

Most shopping malls are open till about 7PM. However, a lot of shops are open till 9PM or longer. The most well-known shops in South Africa are Pick and Pay, Checkers, Spar and Woolworths.