BAS Mistakes? How to Correct Errors Quickly & Avoid ATO Penalties
Making a mistake on your Business Activity Statement (BAS) can feel overwhelmingโespecially when dealing with the ATO. But hereโs the reality: BAS errors are very common among small businesses in Australia, and most are easy to fix when handled correctly.
Whether itโs a GST miscalculation, incorrect PAYG reporting, or a missed transaction, acting quickly is the key to avoiding penalties and staying compliant.
In this guide, TitanTax explains:
- Common BAS mistakes
- How the ATO treats errors
- Step-by-step BAS correction process
- When to revise or adjust your BAS
- Tips to avoid future mistakes
Common BAS Mistakes
BAS mistakes happen more often than you thinkโespecially for busy business owners.
Most common BAS errors include:
- Incorrect GST calculations (overclaiming or underreporting)
- Reporting GST or PAYG in the wrong period
- Payroll errors (wrong PAYG withholding or super)
- Missing transactions or duplicate entries
- Poor record-keeping and lost receipts
Even small errors can lead to discrepancies and ATO follow-ups if not corrected.
Does the ATO Penalise Honest BAS Mistakes?
The Australian Taxation Office (ATO) understands that mistakes happen.
If you:
- Identify the error yourself
- Act quickly
- Voluntarily correct it
๐ You can often avoid penalties completely.
However, penalties may apply if:
- Errors are repeated
- There is negligence
- The mistake appears intentional
The sooner you fix the issue, the lower the risk of interest or fines.
Step-by-Step: How to Fix a BAS Mistake
Follow this simple process to correct BAS errors:
1. Identify the Error
Review your BAS, invoices, receipts, and payroll records to find incorrect figures.
2. Understand the Type of Error
Determine if the issue relates to:
- GST
- PAYG withholding
- PAYG instalments
3. Decide: Adjustment or BAS Revision
- Minor errors โ Adjust in your next BAS
- Major errors โ Lodge a BAS revision
4. Access the ATO Portal or Contact an Agent
Log in to the ATO Business Portal or work with a registered BAS agent like TitanTax.
5. Submit the Correction
Lodge a revised BAS or include adjustments in your next statement with accurate figures.
BAS Revision vs Adjustment: Whatโs the Difference?
Choosing the right correction method depends on the size of the error:
โ Adjustment (Next BAS)
- Small mistakes
- Minor GST differences
- Missed transactions
โ BAS Revision
- Large errors
- Incorrect reporting periods
- Significant GST or PAYG discrepancies
Time Limits:
- Turnover under $20M โ Up to 4 years
- Turnover $20M+ โ Up to 18 months
What Happens After You Submit a BAS Correction?
Once submitted:
- The ATO reviews your correction
- Processing may take a few days (or longer)
- Youโll receive confirmation
Sometimes, the ATO may:
- Request additional details
- Ask for supporting documents
Staying organised reduces delays and complications.
Tips to Avoid BAS Mistakes in the Future
Preventing BAS errors is easier than fixing them.
Best practices:
- Reconcile accounts regularly
- Use cloud accounting software (Xero, MYOB, QuickBooks)
- Keep receipts and records organised
- Stay updated with ATO rules
- Work with a professional BAS agent
When to Get Professional Help
If BAS errors keep happening or things feel too complex, itโs time to get help.
A professional can:
- Fix errors quickly
- Lodge BAS revisions
- Communicate with the ATO on your behalf
- Ensure full compliance
Need Help Fixing BAS Errors?
At TitanTax, we help Australian businesses correct BAS mistakes, stay compliant, and reduce stress.
๐ Call Us: 0457 696 620
๐ง Email: info@titantax.com.au
๐ Address: Unit 14, 164 Government Road, Richlands QLD 4070
Get expert support today and fix your BAS the right way.
FAQs
What happens if I make a mistake on my BAS?
You can correct it through a BAS revision or adjustment. Acting early reduces penalties and keeps your records accurate.
How do I correct BAS with the ATO?
You can lodge corrections via the ATO Business Portal or through a registered BAS agent.
How do I revise BAS online?
Log in to the ATO portal, select the relevant BAS period, and follow prompts to submit corrected figures.
How far back can BAS be amended?
Generally, up to 4 years for small businesses, depending on turnover and ATO rules.
