Cash rounding is required when the lowest physical denomination of currency, or the smallest coin, is higher than the minimum unit of account.
For example, some countries require their companies to round up or down the total amount of an invoice to the nearest five cents, when the payment is made in cash.
Go to Accounting ‣ Configuration ‣ Settings and enable Cash Rounding, then click on Save.
Go to Accounting ‣ Configuration ‣ Cash Roundings, and click on Create.
Define here your Rounding Precision, Rounding Strategy, and Rounding Method.
Odoo supports two rounding strategies:
Add a rounding line: a rounding line is added on the invoice. You have to define which account records the cash roundings.
Modify tax amount: the rounding is applied in the taxes section.
When editing a draft invoice, open the Other Info tab, go to the Accounting Information section, and select the appropriate Cash Rounding Method.