Can we add a second invoice number? as to see the internal invoice number and the invoice number of the customer or supplier

Good day, andres-sandi-cr-,

Yes, you can add a second invoice number to see both the internal invoice number and the invoice number of the customer or supplier.

To do so, you'll simply need to add a custom field for this entry to appear on the form. Let me show you how:

1. Go to Settings ⚙️, then choose Account and Settings.
2. Click Sales under Accounts and Settings, then go to the Sales form content section.
3. Select the pencil icon in that section.
4. Enter a Name into each dialogue box beneath the heading Custom fields and select whether you want the field to be internal (only displayed in QuickBooks), or public (displayed in QuickBooks and displayed/printed on sales forms).
5. Select Save and then Done.
6. These fields will now appear on your sales forms.

Always remember:

• If nothing is entered in the custom fields on a specific sales form, the field will not print.
• Editing the checkboxes and names in the custom forms styles section of QuickBooks will change all custom form styles custom fields on the Sales transaction. 

I've also added the Customise invoices, estimates, and sales receipts in QuickBooks Online in case you need to personalise your sales forms.

Let me know if there's anything else you need by clicking the reply button. I'm always around to help.