It is the month of February, you have just made a sale and your customer would like to immediately receive his sales invoice. But the accounting period for January, is not yet closed, meaning you still have to create sales invoices with regard to your previous accounting period. Normally you would have to wait to give your customer his invoice, as it is forbidden to mix sales invoices over different accounting periods. You have to let the sales invoice numbers increment by one over the different accounting period.

At first sight it seems impossible to create a sales invoice for a next accounting period, until you have processed al your invoices of the previous one. It is possible to make some development changes, but this problem can easily be solved by adjusting the format of your number series linked to your posted sales invoices in Microsoft Dynamics Nav.

For instance if your starting no. of your posted sales invoices is 103001 it would be impossible to create a sales invoice for February without finishing all the invoices for January.

On the other hand if your starting no. is 2007/01/001 with starting date 01/01/2007 and 2007/02/01 with starting date 01/02/2007, you can both create invoices for January and February.

So, by setting a different starting no with different starting dates, matching your accounting period, you can subsequently create sales invoices in a current and previous accounting period.