For each AR company you set up, you can specify whether to manually assign invoice numbers or have them generated automatically.

The Automatically Number Invoices checkbox (AR Company Parameters, Info tab) determines whether invoice numbers will be generated automatically.

If selected, each time you enter an invoice (in AR Invoice Entry), the system will automatically assign the next sequential invoice number based on the Last Invoice Number (Info tab). If not selected, you must enter invoice numbers manually.

If you are using the Job Billing and/or Material Sales modules and you elect to use the AR numbering scheme for invoices created in those modules, the system will automatically include all invoices created in AR, JB, and MS when determining the next sequential number to use.