When entering time you will see an Override box next to the Billable (hrs). This allows you to bill only a portion of the entry. You can enter the amount of Labor (hrs), then check the Override box next to Billable (hrs) and change the amount that you want to be billable. You can track that you worked 4 hrs for example but are only billing for 2. Once you check the box next to Override you can then enter in a description in the Reason box but this is not required and does not show on the invoice for the client to see.