What Happens If I Don't Have an ABN on My Invoice in Australia?

By Dan Reeve — Working handyman and founder of SMASH Invoices. Built SMASH after losing $1,200 in uninvoiced jobs in a single year. He still takes on handyman work and uses SMASH on every job. About Dan →

If you invoice without an ABN in Australia and the invoice total is over $75, the customer is legally required to withhold 47% of the payment and send it to the ATO. This is called the Pay As You Go (PAYG) withholding obligation. You can reclaim the withheld amount via your tax return, but it creates a cash flow problem and signals non-compliance. An ABN is free and takes approximately 15 minutes to apply for at abr.business.gov.au.

Why the 47% withholding rule exists

The ATO introduced ABN withholding to prevent payments to unregistered, untraceable businesses. If a customer pays someone without an ABN, there's no guarantee the income will be reported or taxed.

The withholding rule makes it the customer's obligation to ensure the ATO gets its share if the supplier doesn't have an ABN.

For you as a sole trader, the practical effect is devastating: you complete a $500 job and receive $265. The other $235 goes to the ATO. You get it back at tax time, but you can't pay your suppliers with a tax refund you'll receive in 10 months.

How to get an ABN

Applying for an ABN is free through the Australian Business Register. You need:

• Tax File Number (TFN)
• Business structure (sole trader)
• Primary business activity (your trade)
• Business address
• Estimated annual income

Processing typically takes up to 28 days but is often approved within minutes for sole traders. Once you have an ABN, it's yours indefinitely, it doesn't expire or need renewal.

ABN vs GST registration — what's the difference?

These are commonly confused:

You need an ABN to do business. You may or may not need GST registration depending on your turnover.

Frequently asked questions

Can I start work before my ABN is approved? Technically yes, but you should inform customers that your ABN is pending and provide the ABN number as soon as it's issued. Many business customers (property managers, real estate agents, body corporates) will not pay without a valid ABN on the invoice.

What if I have an ABN but it's not on my invoice? Technically non-compliant, the withholding obligation still applies. Make sure your ABN appears on every invoice. Invoicing apps like SMASH Invoices store your ABN in your profile and include it on every generated invoice automatically.

Do I need an ABN to invoice cash-in-hand jobs? You need an ABN for all business activity regardless of payment method. Cash income must be reported on your tax return. An ABN signals legitimate business operation. Running without one exposes you to both withholding problems with customers and ATO scrutiny.

How do I check if my ABN is correct on invoices? Your ABN is the 11-digit number registered in your name at abr.business.gov.au. You can look up any ABN to verify it's active and registered to the correct entity. Customers can do the same, if your ABN lookup shows a different name than on your invoice, it creates doubt.

What if a customer withholds 47% despite me having an ABN? If your ABN is clearly displayed on the invoice and the customer withholds anyway, they are in breach of their payment obligation. You can pursue the outstanding amount through normal debt recovery, small claims tribunal, formal demand letter, or a collection service depending on the amount.

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Internal links: What must be on a tax invoice in Australia? · How to invoice as a handyman in Australia