In order to best meet the needs of your law firm, Wise Owl Legal allows you to not only create invoices through selecting billed time but also allows you to create an 'invoice on the fly'. This is useful when a client comes in for an hour or two consultation and you want to bill them straight away and do not expect to do any further work for them. Therefore to save time an invoice can be created without first entered in time.
WARNING: This format is NOT recommended for multi-line invoices. Please enter multi-line invoices via Time entry; Fixed Fees; Disbursements and Recoveries sections.
Select the accounting and finance module from the top menu bar.
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From the invoicing section, select the drop-down arrow next to new invoice and select blank invoice. 
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Note that this blank invoice is only available for professional fees. 
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Fill in the fields as per a standard invoice.