If Multi-Currency has not been enabled:

From Oracle NetSuite to Bill.com

• Transactions in Oracle NetSuite that are not in USD (US dollar) will not sync to Bill.com, unless Multi-Currency is enabled in both Bill.com and Oracle NetSuite.

From Bill.com to Oracle NetSuite

• Transactions in Bill.com will always sync to Oracle NetSuite in USD, unless Multi-Currency is enabled in both Bill.com and Oracle NetSuite.