Hi there sales-tsquaredto,
It's important that all your transactions are entered correctly for your books to be well balanced. QuickBooks Online is a great tool able to help keep track of sales and expenses so you can see the profit of your company. I can provide some information about billable expenses.
If you want to only invoice a part of the items due to not receiving the rest of the pieces, the first thing that will need to be done is to go to the original bill, and split the line containing 11 widgets into two separate lines, one containing 6, the other containing the 5 remaining. Both would be billable in the same way that the original line.
Then, go to create an invoice for your customer, selecting only the 6 widgets intended to be invoiced and packed, then, in a second line, don't choose the other billable expense, choose to only add a description for this line with no product, amount, rate and tax. In this description, you can add something along the lines of 5 Widgets backordered, or 5 Widgets remaining. This line won't affect your books if its only content is the description, but will show on the packing slip. You can then choose to invoice the rest later.
If you want to invoice it all at once, then you can once again split up the lines on the bill, then when creating the invoice, add both billable expense lines, but for the second line, in its description, add the description backorder.
If you have any other questions, feel free to reach out here.
