What is an invoice number

An invoice number is a unique identifier that must be assigned to every invoice or bill to align with the requirements stipulated by Australian accounting legislation. An invoice, to be recognised as a legitimate financial document, must bear such a number, which is subject to specific regulations for validity and traceability.

What is an invoice number

An invoice number is a unique identifier that must be assigned to every invoice or bill to align with the requirements stipulated by Australian accounting legislation. An invoice, to be recognised as a legitimate financial document, must bear such a number, which is subject to specific regulations for validity and traceability.

The Australian accounting standards dictate that sales documents are to be sequentially pre-numbered using machine assignment or be distinctly marked in a manner that allows for complete and effortless verifiability of all issued sales transactions.

The Imperative of Sequential Invoice Numbering

For effective financial management and auditing, each invoice dispatched must carry a distinctive number in a continuous series. This sequence can commence with any number the issuer finds suitable, but it must progress in an unbroken numerical fashion for successive invoices. Common starting points range from ‘1’ to ‘1001’, followed by each subsequent invoice taking the next numerical value in sequence.

When transitioning to a new invoicing software, it’s crucial that the first invoice issued on the new platform picks up the sequence from the last number utilised in the former system. For example, should the last invoice be labelled ‘1089’, the following invoice should be marked as ‘1090’.

Since a seamless numerical progression is mandated, the cancellation or amendment of an already issued invoice is prohibited. Should an invoice contain inaccuracies, the correction process involves the issuance of a credit note.

Utilising Compliant Invoicing Software

To guarantee compliance, invoice numbers should be generated via an automated system or pre-embedded on invoice forms. Employing certified invoicing software is the simplest method to ensure adherence to these regulations.

Platforms like Conta automatically produce an invoice number every time a new invoice or credit note is generated, relieving the user from manual compliance checks.

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Invoicing Outside of Software Solutions

Regarding utilising invoice templates or personally crafted invoices in software like Word, such practices are not permissible under Australian law. The flexibility to alter invoices post-issuance and the absence of sequential pre-numbering contravene regulations.

The only allowable alternative to invoicing software is the use of pre-numbered physical invoice forms, an approach reminiscent of traditional accounting practices. This historical method complies with the stringent requirements of sequential numbering, thereby preserving the integrity of accounting records.