3622247 - Only 3 currencies are supported in SAP S/4HANA Cloud Public Edition

• Is it possible to have a second freely defined currency assigned to the company code? 
• If the Functional Currency is independent from the freely definable one? For example, is it possible to set SGD as the company code currency, EUR as the group currency, PHP as the freely defined currency, and USD as the Functional Currency? 

 SAP S/4HANA Cloud Public Edition

The answers are No.

In Public Cloud only 3 currencies are supported – 10(company code currency), 30 (Group Currency) and 3^rd currency (Freely-Defined Currency). Any of these can defined as functional currency.
Note that you can only create one additional currency type per company code. see reference in SAP Help Portal: Create Additional Currency Types

A complete picture regarding supported currencies in Public Cloud can be found as help documentation: Currencies

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