- Reactivating a cancelled ABN is not a switch you flip. You submit a fresh application through the ABR, your eligibility is reassessed from scratch, and if your business structure has not changed, you will typically get your original ABN back.
- Your GST registration does not reinstate automatically when your ABN is reactivated. It must be set up again as a separate step, and if you were trading above the $75,000 threshold during the gap period without GST registration, you may have a backdated liability to address.
- A cancelled ABN does not wipe your tax obligations. Any income earned, GST collected, or employee payments made while your ABN was active remain subject to standard tax treatment, and trading while cancelled creates compliance exposure for both you and your clients.
If your ABN has been cancelled in Australia, the good news is you can get it back. In most cases, reactivating a cancelled ABN is a straightforward process and if you’re re-registering the same business entity, the Australian Business Register (ABR) will typically reissue your original ABN number.
That said, it’s not as simple as flipping a switch. A cancelled ABN doesn’t reinstate itself, you need to submit a new application through the ABR, confirm you still meet the eligibility criteria, and sort out a few things afterwards that most guides don’t mention, like GST re-registration and your tax position during the gap period.
This guide walks you through everything: whether you’re eligible to reactivate, the 4 steps to reactivate your ABN in Australia, and what to do once it’s back and active.
Before submitting your reactivation application, update your ABR details first. Outdated contact information is one of the most common reasons ABNs get cancelled, and submitting the same stale details again can push processing time from hours to up to 20 business days.
Can you reactivate a cancelled ABN in Australia?
Yes, but “reactivation” isn’t quite how it works.
The ABR doesn’t switch your ABN back on. Instead, you submit a new ABN application, and your eligibility is reassessed based on your current situation.
If you’re registering the same legal entity, for example:
- the same sole trader (same TFN), or
- the same company (same ACN)
the ABR will usually reissue your original ABN.
Will you get the same ABN back after reactivation?
If your business structure hasn’t changed, your original ABN is typically reinstated.
For example:
- You were a sole trader before, and you’re returning as a sole trader
In this case, the ABN stays the same because it’s tied to your legal entity, not when you were active.
When will you receive a new ABN instead?
If your business structure has changed, you’ll be issued a new ABN.
For example:
- You previously operated as a sole trader
- You’re now setting up a company
A company is a separate legal entity, so it gets its own ABN, derived from its ACN.
Why was your ABN cancelled?
Before reactivating, it helps to understand why your ABN was cancelled in the first place because in some cases, the reason affects what you need to do before reapplying.
1. ABR-initiated cancellation:
This is the most common scenario.
- The ABR regularly reviews the register and cancels ABNs that show signs of inactivity, no BAS lodgements, no tax returns, no detectable business activity.
- The ATO shares data with the ABR to identify these cases.
- Many business owners only discover their ABN has been cancelled when a client flags it or a transaction is rejected.
Cancellations also happen when the ABR sends a review notice and receives no response often because contact details on the register were outdated. The ABR treats non-response as confirmation that the business is no longer active.
2. Voluntary cancellation:
You or your accountant notified the ABR that your business was closing or pausing.
- This might have happened when you took an extended break, went back to employment, or wound down a side business.
- If this is your situation, reactivation is typically the most straightforward, you paused voluntarily and now you’re returning.
3. Structure change:
You changed your business structure, for example, moving from a sole trader to a Pty Ltd company.
- In this case, your old ABN was cancelled and a new one was issued for the company entity.
- If you’re returning to operate as the same structure you previously used, this is still a standard reactivation.
- If the structure is changing again, you’re applying for a new ABN rather than reactivating an old one.
Read more: What Is the Best Business Structure in Australia?
4. Compliance-related cancellation:
If your ABN was cancelled as part of an ATO compliance or enforcement action, do not simply reapply without first resolving the underlying issue. Seek professional advice before proceeding, reapplying without addressing the root cause can compound the problem.
Are you eligible to reactivate your ABN?
The ABR assesses every ABN application on current eligibility criteria, not on the basis that you previously held one. Having had an ABN before does not guarantee reactivation. Before lodging your application, confirm you meet the following:
Who can reactivate an ABN in Australia?
- You are currently carrying on, or genuinely intending to carry on, an enterprise in Australia
- You are a recognised entity type: sole trader, company, partnership, trust, or other qualifying body
- You have an Australian TFN (for individuals) or ACN (for companies)
- Your previous ABN was not cancelled due to fraud, misrepresentation, or an unresolved ATO compliance action
When can your ABN reactivation be rejected?
- You are not yet actively carrying on a business or have no imminent intention to do so
- Your cancellation was related to a formal ATO compliance matter that has not been resolved
- You are changing structure in which case you need a new ABN application, not a reactivation
If you’re unsure whether you qualify, speaking to an accountant before applying is worthwhile; a rejected application creates a record and may delay the process further.
Many ABN cancellations are not triggered by anything the business owner did wrong. The ABR runs automated inactivity reviews using ATO data, and a cancelled ABN is often the result of nothing more than a review notice sent to an outdated email address that went unanswered.
The 4 steps to reactivate your ABN in Australia
Reactivating your ABN is straightforward as long as you follow the right steps.
Step 1: Check your ABN status
Start by confirming your ABN is actually cancelled.
- Go to Australian Business Register
- Search your ABN or business name
- Check the status and cancellation date
Why this matters:
- It shows how long your ABN has been inactive
- It helps identify if you traded during the gap (which has tax implications)
While you’re there, review your details (address, contact info, business activity).
Outdated information is a common reason ABNs get cancelled and submitting the same details again can cause delays.
Step 2: Get your details ready
Before applying, gather everything you’ll need:
- TFN (for sole traders)
- ACN (for companies)
- Contact details (email, phone, postal address)
- Business address (must be a physical Australian address)
- Business activity (selected using ANZSIC categories)
- myID login (for identity verification)
If you don’t have a myID, set it up first, it’s free and speeds up approval significantly.
Without it, your application may take up to 20 days instead of hours.
Step 3: Submit a new ABN application
To “reactivate” your ABN, you’ll need to apply again through the ABR and submit a new application. Select the same business structure as before.
This is important, choosing a different structure may result in a new ABN instead of your original one.
Processing time:
- Instant to 24 hours (with verified myID)
- Up to 20 days (if manual review is required)
Once approved, your ABN becomes active immediately.
Cost: Free
Step 4: Update your details and notify others
Reactivating your ABN is just the first step, now you need to get your business fully operational again.
Make sure you:
- Update the ABR register
Keep your details accurate to avoid future cancellations - Notify clients and suppliers
Especially anyone who pays or invoices you - Update business documents
Invoices, contracts, website, email signatures - Inform your bank
If your account is linked to your ABN - Re-register for GST (if required)
This depends on your turnover and previous registration status
Important:
If you invoice without a valid ABN, the payer may be required to withhold 47% of your payment under no-ABN withholding rules.
Do you need to re-register for GST after reactivating your ABN?
This is the question most reactivation guides skip entirely, and it’s one of the most common sources of compliance problems for returning business owners.
1. GST registration does not reinstate automatically when your ABN is reactivated.
If your ABN previously had GST registration attached and it was cancelled along with the ABN, you must re-register for GST as a separate step.
2. When GST re-registration is mandatory:
If your annual business turnover is $75,000 or more (or $150,000 for non-profit organisations), GST registration is a legal requirement. As soon as your ABN is active and you’re trading at or above these thresholds, re-register for GST through the ABR or ATO online, don’t wait.
When GST re-registration is optional:
If your turnover is under $75,000, GST registration is your choice. That said, it’s worth considering even at lower turnover levels if you deal with GST-registered clients, want to claim GST credits on business purchases, or expect to grow past the threshold within the next 12 months.
The backdating risk:
If there was a period where you were trading above the GST threshold without a valid GST registration because your ABN was cancelled and GST lapsed, the ATO can assess GST liability for that period. This is not automatically flagged, but it is an exposure that exists. If this applies to your situation, review it with an accountant before assuming you’re in the clear.
PAYG withholding:
If you have employees or contractors, confirm your PAYG withholding registration is active after reactivation. Like GST, PAYG withholding obligations do not automatically reinstate when an ABN is reactivated.
What happens if you traded while your ABN was cancelled?
A cancelled ABN does not erase your tax obligations for any period your business was active. Any income earned, GST collected, or employee payments made while the ABN was active remain subject to standard tax treatment, cancellation doesn’t change that.
- The more complex scenario is if you continued trading after your ABN was cancelled, even inadvertently.
- Clients who paid you without a valid ABN on your invoice were technically required to withhold 47% of the payment under the no-ABN withholding rules.
- Whether they did or not, the underlying tax obligations on that income still exist.
If there was a meaningful gap between cancellation and reactivation during which you continued operating, it’s worth sitting down with an accountant to review your position for that period before lodging any outstanding returns or activity statements. Getting ahead of it is always better than waiting for the ATO to raise it.
What are the common mistakes when reactivating ABN?
1. Assuming the ABN reinstates automatically
It doesn’t, not after a voluntary cancellation, not after an ABR-initiated one. You must submit a new application every time, regardless of the reason for cancellation or how recently it happened.
2. Submitting the application with outdated details
The same outdated contact details that caused the original cancellation will create problems again. Review and update every field before lodging, address, email, phone, business activity, and authorised contacts.
3. Forgetting to re-register for GST
This is the most common post-reactivation oversight. Your ABN being active again does not mean your GST registration is active. If you’re required to be GST-registered, do this as a separate step immediately after your ABN is confirmed.
4. Trading with a cancelled ABN without realising it
If you’ve been issuing invoices or receiving payments without an active ABN, you may have created withholding tax complications for your clients and a compliance gap for yourself. Don’t ignore this, address it with your accountant as part of the reactivation process.
5. Applying without resolving an underlying compliance issue
If your ABN was cancelled as part of an ATO enforcement or compliance matter, submitting a new application without addressing the root cause will likely result in rejection and may escalate the situation.
If your ABN was cancelled as part of an ATO compliance or enforcement action, do not submit a reactivation application without resolving the underlying issue first. Reapplying without addressing the root cause will likely result in rejection and may escalate the matter.
How Sleek can help?
Sleek helps Australian businesses get set up correctly and stay compliant, from company registration through to ongoing accounting and tax.
Fast company setup: Register your company with ASIC, secure your ACN, and get your ABN, TFN, GST, and PAYG sorted so you can start trading right away.
- All-inclusive accounting and compliance support: From bookkeeping and BAS to payroll and tax compliance, Sleek keeps your business on track.
- Transparent Pricing: Every service comes with clear, upfront pricing. No hidden fees, no surprises.
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Frequently Asked Questions
Will I get my old ABN number back when I reactivate?
In most cases, yes, provided your business structure hasn’t changed. The ABN is tied to your legal entity (your TFN as a sole trader or ACN as a company), so re-registering the same entity typically returns the same number. If your structure has changed, you will receive a new ABN.
How long does ABN reactivation take?
For online applications submitted with a verified myID and complete information, most decisions are immediate or within 24 hours. Applications requiring manual review can take up to 20 days. Having your TFN or ACN, current contact details, and myID ready before you start minimises delays.
What happens to my GST registration when my ABN is cancelled?
GST registration is cancelled along with the ABN in most cases. When you reactivate your ABN, GST does not reinstate automatically you must re-register separately through the ABR or ATO if your turnover requires it or if you choose to register voluntarily.
