How Xero invoice numbers are decided

By default, when we send orders from Onsight to Xero, the invoice number field in Xero will be the next sequential invoice number. This is because invoice numbers are meant to run sequentially for auditing purposes. If you prefer, the Onsight order number or quote number can be configured to override the next sequential invoice number in Xero. Please contact [email protected] to request this.

The next sequential invoice number in Xero can be found by going to:

Settings
Organisation settings
Invoice settings
Default settings

Look at the fields: Invoice Prefix and Next Number: