Admin users can create custom invoice prefixes for different contracts.
Go to System Admin [3] Types Contracts [1] Add [2]/Edit Contracts popup
The Description [1] data entry field and the Invoice prefix [2] data entry field can be alphanumeric with a 25 character/number limit.
The Invoice number length [3] is limited from 1 to 12, for example:
Invoice number length set to 3.
Invoice start number [4] range is limited from 1 to 999.
To generate an invoice, please use Quick Ref Create an invoice.