A few simple step to add new currency (ISO) code to your system.
The first you need to do is to go to SPRO >> General Settings >> Currencies >> Check Currency Codes
This is where the system stores all the currencies which required in your business transactions.
Standard settings: In SAP standard system, all currencies are defined according to the international ISO standard.
It is recommends that you use the ISO standard for your additional entries.
Entries that do not correspond to the ISO standard, will not be able to use standard data exchange in international communication (e.g. bank clearing transactions).
Let say you're required to add new currencies to the system, for example:-
Currency CZK
Long Text Czech Krona
Alternative key 203
Once done, save the entries