31 March Tax Deadline: Avoiding Penalties for Late Tax Payer Lodgment in Sydney
- Sash Denkovski
- 4 days ago
- 3 min read
The 31 March tax deadline is a critical cutoff for large Australian entities, including companies and SMSFs with a total income over $2 million, and individuals or trusts with a tax liability exceeding $20,000. Missing this date results in ATO Failure to Lodge (FTL) penalties starting at $330 per 28-day period. For expert assistance in meeting these deadlines, Contact Adenix Accounting Sydney.
Why the 31 March Date is Critical for Your Business
Australian entities, including companies and SMSFs with a total income over $2 million, and individuals or trusts with a tax liability exceeding $20,000. Missing this date results in ATO Failure to Lodge (FTL) penalties starting at $330 per 28-day period. For expert assistance in meeting these deadlines, Contact Adenix Accounting Sydney.
Who Must Avoid a Late Tax Payer Lodgment on 31 March?
The ATO registered agent lodgment program specifies that this deadline isn't for everyone, but for those it does affect, the rules are strict.
Large Entities and Companies
If your company or Self-Managed Super Fund (SMSF) had a total income of $2 million or more in the latest year lodged, March 31 is your final deadline.
High-Liability Taxpayers
This date also applies to individuals and trusts (excluding medium/large trusts) whose latest tax return resulted in a tax liability of $20,000 or more
The Risks of Late Tax Payer Lodgment on 31 March
If you find yourself categorized as a late taxpayer, the ATO’s automated penalty systems kick in.
ATO Penalties for Late Taxpayer Lodgment on 31 March
As of 2026, the penalty for a small entity is $330 for every 28 days the return is overdue. The total financial impact of a late tax payer lodgment on 31 March can quickly exceed several thousand dollars for larger businesses once the General Interest Charge (GIC) is applied.
Medium Entities: $660 per period (up to $3,300)
Large Entities: $1,650 per period (up to $8,250)
General Interest Charge (GIC) and Audits
In addition to flat fines, the ATO applies a compounding General Interest Charge on any unpaid tax. Consistently missing deadlines like the 31 March cutoff also increases your Audit Risk Profile, signaling to the ATO that your Business Accounting processes may be insufficient.
How Adenix Accounting Helps You Stay Compliant
With over 18 years of experience, our team provides specialized Business Advisory and tax services to keep your records spotless.
Penalty Remission: We negotiate with the ATO to have penalties waived if you have a reasonable excuse for late lodgment.
Catch-up Bookkeeping: Using modern cloud accounting tools, we help you reconstruct missing records fast.
Flexible Appointments: We understand the Sydney hustle. We offer after-hours and weekend appointments to suit your schedule.
FAQ: Everything You Need to Know
Q: Can I get an extension for the 31 March tax deadline?
A: Yes, but you must act before the deadline. As registered tax agents, Adenix Accounting can apply for lodgment deferrals based on unforeseen circumstances.
Q: What happens if I can’t pay my tax bill by March 31?
A: You should still lodge on time. Lodging avoids the "Failure to Lodge" penalty. We can then help you set up an ATO payment plan to manage the debt.
Q: Does this deadline apply to my new startup?
A: Most new startups have until 15 May, but if you have outstanding prior-year returns, your deadline may be earlier. Check your status with our Tax Return Specialists.
Take Control of Your Tax Today
Don’t let the 31 March deadline become a financial burden. Whether you are in Rockdale, the Sydney CBD, or operating remotely, Adenix Accounting is your partner in compliance.
Visit Adenix Accounting Sydney
Our office is located in the heart of the St George district. We proudly support local entrepreneurs across Rockdale, Kogarah, and the Sydney CBD.
Getting Here: Our office is just minutes from the M5, making it easy for busy directors to drop off records or attend a strategy session.