How do I auto-populate the “Sales Order Number” or “Sales Order Reference Number” from a sales order to an invoice?
The Order Number field, in Zoho Books, is an optional field on the invoice creation page. While converting a sales order into an invoice, Zoho Books auto-populates the Order Number field with the value of Sales Order Number by default. If necessary, you can change this preference to auto-populate the value of Sales Order Reference Number. Here’s how:
- Go to Settings by clicking the Gear icon in the top right corner.
- Click Invoices under Sales.
- Choose the option Use Sales Order Number or Use Sales Order Reference Number under Invoice Order Number.
- Click Save.

Now, whenever you convert a sales order into an invoice, the Invoice Order Number field in the invoice will be auto-populated with the Sales Order Number or Sales Order Reference Number.