7 ABN Registration Mistakes to Avoid (And How to Fix Them)

If you're applying for an ABN, it’s important to get it right the first time. Small mistakes can lead to delays, rejected applications, or ATO follow-ups.

In this article, we’ll walk through:

• Choosing the wrong business structure
• Entering incomplete or incorrect information
• Using vague business activity descriptions
• Leaving out your Tax File Number (TFN)
• Using unreliable contact details
• Ignoring GST registration requirements
• Assuming you don’t need an ABN

Looking to get started right away? Get your ABN online with Register My ABN today – it takes less than 5 minutes.

1. Choosing the wrong business structure

Many people accidentally select “Company” or “Partnership” when they’re actually applying as a sole trader.

If you’re running the business as an individual, choose Sole Trader. You can always change your structure later if your business grows.

Read more on the ATO’s guide to sole trader structures.

2. Entering incomplete or incorrect information

Simple mistakes in your application can trigger a manual review or rejection.

Before submitting your ABN application, double-check:

• Your full legal name and date of birth
• Your Tax File Number (TFN)
• Your business or home address
• Your email and phone number

Even small errors, like a missing field or typo, can delay your ABN approval.

Need help making sure your application is correct? 👉 Follow our step-by-step guide to apply for a sole trader ABN the right way

3. Using vague business activity descriptions

The ATO requires a clear, specific description of your business activity.

Avoid generic labels like “consultant” or “freelancer”. Be specific, for example:

• “Bookkeeping services”
• “Food delivery driver”
• “Computer or IT consulting service”

You can find guidance on describing your business activity in the ABR application checklist.

4. Leaving out your Tax File Number (TFN)

Technically, you can apply without a TFN, but it often leads to additional identity checks and a slower process, which can take up to 20 business days.

Including your TFN:

• Helps verify your identity
• Speeds up ABN approval
• Reduces the chance of rejection or delays

5. Using unreliable contact details

The ATO will use your contact details to send important documents, including your official ABN letter.

Avoid:

• Using someone else’s address
• An email you rarely check
• A phone number you don’t use anymore

Make sure your address, email, and phone number are all current and reliable.

6. Ignoring GST registration requirements

If your business earns, or is likely to earn, over $75,000 per year, you must register for GST. If you don’t register and pass the threshold later, you may face penalties or compliance issues.

Learn more about whether you need GST here.

7. Assuming you don’t need an ABN

Even if you’re working casually or part-time, you may still need an ABN if:

• You issue invoices
• You advertise your services
• You regularly earn income as a contractor, freelancer or gig worker

The ATO considers these indicators that you’re carrying on a business, which means you’ll need an ABN to operate legally.

Conclusion

Getting your ABN right the first time can save you from delays, compliance issues, and unnecessary stress.

Start your business with confidence and avoid the common mistakes that can slow you down.

Need an ABN? Apply through Register My ABN for an ABN in less than 5 mins for $45 (incl. GST), which is fully tax-deductible.