ABN Cancelled? Here’s How to Reactivate It Quickly

If you’ve discovered your ABN has been cancelled, it can feel stressful - especially if you’re trying to get paid or invoice clients.

The good news? In many cases, you can get your ABN back - either by reactivating it or by applying for a new one.

In this article, we’ll explain:

• Why the ATO cancels ABNs (sometimes without notice)
• How to check if your ABN has been cancelled
• How to reactivate or reapply for your ABN online
• What to do if you no longer need your ABN

Why your ABN may have been cancelled

The ATO cancels ABNs if they believe the business is no longer active.

This could happen if:

• You haven’t lodged a tax return as a sole trader
• You haven’t issued invoices or made sales for over 2 years
• Your business hasn’t responded to ATO review requests
• You’ve advised the ATO that you’ve stopped trading

Even if you're still working part-time or intermittently, the ATO may assume you're no longer in business unless there’s clear activity.

How to check if your ABN is cancelled

You can use the ABN Lookup tool to search your ABN.

If your ABN:

• Shows "Cancelled" in the status column → it’s no longer active
• Returns no results → it may have been cancelled a while ago or never activated

If cancelled, the ATO usually sends a letter or email. Sometimes, the business owner misses this if their address or contact details are outdated.

What to do if your ABN is cancelled

There are two options:

1. Reactivate the same ABN

You may be able to reactivate your original ABN if your business structure and details haven’t changed.

To do this:

• Log in to the ABR website with your myGovID
• Submit a reactivation request via the "Update ABN" function
• Alternatively, ask your accountant or tax agent to reactivate it for you

Reactivation can take up to 20 business days and may require additional information.

2. Apply for a new ABN

If your business details have changed, or if the reactivation process is delayed, it’s often easier to apply for a new ABN.

Use Register My ABN to get a new ABN in minutes - faster, simpler, and made for sole traders.

When should you NOT reactivate an ABN?

You should consider applying for a new ABN instead of reactivating if:

• You’ve changed from a sole trader to a company or partnership
• You want a faster resolution and your structure hasn't changed
• You were previously inactive for a long period and need a clean slate

The ATO allows reapplications if you’re starting or restarting business activity.

Don’t let a cancelled ABN delay your business

A cancelled ABN doesn’t mean the end of your business - just that the ATO thinks you’re no longer trading. If that’s not the case, you can either reactivate your existing ABN or apply for a new one and get back on track fast.

Need to apply for a new ABN today? Register My ABN offers fast, easy ABN registration for sole traders - no paperwork or waiting around.