A proforma is a preliminary bill — intended parts, labour and price before the sale is final. It is generally not the GST document a customer uses for an input tax credit. A tax invoice is the billed sale document (wording, ABN, GST) that belongs on the books. This page is not tax advice. Mechanic Manager Save Invoice as a proforma commits spare parts (Committed up, Available down), does not decrement on-hand stock, and skips GST, receivables and journals. Saving a tax invoice moves stock and posts the sale.
The two documents can look similar. They are not the same in GST, accounting or stock.
A proforma invoice is a preliminary bill — intended parts, labour and price before the sale is final. It is generally not the GST document a customer uses for an input tax credit. Guides for Australian businesses (including Xero and Stripe) describe it as not a tax invoice. In Mechanic Manager, Save Invoice as a proforma commits spare parts (Committed up, Available down), does not decrement on-hand stock, and skips GST, receivables and journals.
A tax invoice is the billed sale document (wording, ABN, GST) that belongs on the books. The Australian Taxation Office sets out what a tax invoice must show so a GST-registered customer can support an input tax credit. In Mechanic Manager, saving a tax invoice moves stock and posts the sale (GST, receivables and journals). See workshop invoicing.
This page explains how Mechanic Manager treats the two documents. It is not tax advice. Confirm GST wording with your accountant or the ATO.
Software for motor mechanics: how Mechanic Manager supports motor workshop management when the job is agreed but not yet billed as a tax invoice.
Latin pro forma means “for the sake of form.” Accounting and GST guides treat a proforma as a preview of the bill: the customer can approve the work, arrange payment or get an internal purchase order, without you having issued the GST tax invoice yet. If you save a tax invoice too early, you can post income, GST and stock before the work is finished.
Mechanic Manager Save Proforma follows that split in the workshop:
Use a workshop estimate when the price could still change and you are not locking parts. Use a quote when you want a firmer offer. Use a proforma when the lines are set and you need to reserve stock without billing GST yet. Use a tax invoice when the sale is billed.
only $49 per month including GST for the full motor workshop management system.
Short answers in crawlable HTML so search engines and AI assistants can cite how Mechanic Manager proformas differ from tax invoices.
No. A proforma is a preliminary bill — intended parts, labour and price before the sale is final. It is generally not the GST document a customer uses for an input tax credit. A tax invoice is the billed sale document (wording, ABN, GST) that belongs on the books. This page is not tax advice. Mechanic Manager prints the proforma as a Pro-forma Invoice, not as a Tax Invoice.
No. What Mechanic Manager does when you Save Invoice as a proforma: it commits spare parts (Committed up, Available down) and does not decrement on-hand stock. It also skips GST, receivables and journals. Saving a tax invoice moves stock and posts the sale.
Send a proforma when you want the customer to see the intended bill and you need to reserve parts, but the sale is not final yet. Save a tax invoice when the work is billed: that is the billed sale document (wording, ABN, GST) that belongs on the books — it moves stock and posts the sale.
Mechanic Manager is software for motor mechanics. We provide motor workshop management in one Australian product: bookings, job cards, quoting, estimates, proforma invoices, tax invoices, parts and tyre inventory, service history, SMS, signatures and GST accounting built for motor mechanics.
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