BAS Lodgement Deadlines in Port Lincoln: What They Are and What Happens If You Miss Them

For Port Lincoln small business owners, BAS lodgement deadlines fall quarterly — on 28 October, 28 February, 28 April, and 28 July. Miss one and you may face a failure to lodge (FTL) penalty of up to $1,650 for small entities, plus daily interest on any unpaid amount.

What Is a BAS and Who Needs to Lodge One?

A business activity statement (BAS) is the form businesses use to report and pay a range of tax obligations to the ATO in one place. If your business is registered for GST, the ATO will automatically issue you a BAS when it is time to lodge.

According to the ATO’s GST registration guidance, you need to register for GST — and therefore lodge a BAS — when your annual business turnover reaches $75,000 or more. Many sole traders and small businesses — from those using bookkeeping services in Port Lincoln to operators across the wider Eyre Peninsula — cross this threshold earlier than they expect.

What does a BAS cover?

Depending on your business, your BAS may require you to report on:

• Goods and services tax (GST) collected and paid
• PAYG withholding — tax withheld from employee wages
• PAYG instalments — prepayments toward your income tax
• Wine equalisation tax (if applicable)
• Luxury car tax (if applicable)
• Fuel tax credits (if applicable)

Quarterly BAS Deadlines: The Key Dates for 2025–26

Most small businesses on the Eyre Peninsula lodge their BAS quarterly. According to the ATO’s BAS due dates guidance, quarterly activity statements are due on the 28th day of the month following the end of each quarter, with one exception for the December quarter.

If you lodge your BAS online through ATO Online Services, you may be eligible for an additional two weeks. Note that the December quarter (Q2) already includes a one-month extension and does not attract a further concession. Registered BAS agents receive their own extended lodgement dates through the BAS agent lodgment program.

What Happens If You Miss a BAS Deadline?

Missing a BAS deadline triggers two separate consequences: a penalty for late lodgement and interest on any unpaid tax. Understanding both will help you act quickly if you find yourself past the due date.

Failure to lodge (FTL) penalty

The ATO’s FTL penalty accrues at the rate of one penalty unit for every 28-day period (or part thereof) that your BAS remains overdue, up to a maximum of five penalty units. Based on the current penalty unit value of $330 (effective 7 November 2024), the maximum FTL penalty for a small entity is $1,650.

It is worth knowing that the ATO will generally contact you — by phone or in writing — before applying a formal FTL penalty. You will usually be allowed to lodge or to explain your circumstances. The penalty may also be partially or fully remitted based on your situation — see the ATO’s guidance on how to request remission of interest and failure to lodge penalties.

General interest charge (GIC) on unpaid amounts

If you owe GST or other amounts on your BAS and don’t pay by the due date, the ATO will automatically apply a general interest charge (GIC). GIC is calculated daily on a compounding basis on the overdue amount. The GIC annual rate is reviewed quarterly by the ATO — for the October to December 2025 quarter, it was 10.61% per annum.

From 1 July 2025, GIC incurred on ATO debts is no longer tax deductible — an additional reason to avoid letting a BAS debt run beyond its due date.

What to Do If You’ve Missed Your BAS Deadline

If you have already missed a BAS due date, acting promptly is the most effective way to reduce the impact. Here is a practical sequence to follow:

1. Lodge as soon as possible. Every additional 28 days adds another penalty unit. The sooner you lodge, the lower your FTL exposure.
2. Pay any amount owing — or part of it. Even a partial payment reduces the balance on which GIC accrues daily.
3. Set up a payment plan if you can’t pay the full amount. The ATO’s payment plan options allow you to spread the debt, though GIC will continue to apply to the outstanding balance.
4. Contact the ATO or speak to a registered BAS agent. If you have a reasonable explanation for the delay — such as illness, a natural disaster, or a system failure — you can request remission of the FTL penalty.

How to Avoid Missing a BAS Deadline

For busy business owners in Port Lincoln, Cummins, Tumby Bay, and Cowell, keeping track of quarterly deadlines on top of running a business can be genuinely difficult. A few practical habits can make a meaningful difference:

• Set calendar reminders two to three weeks before each due date — not on the due date itself.
• Keep your records current throughout the quarter. Scrambling to reconcile months of transactions in the final week is a common cause of late lodgements.
• Lodge online to take advantage of the automatic two-week extension available for most quarters.
• Use a registered BAS agent. Working with a local BAS agent means your BAS is managed under the BAS agent lodgment program, which provides extended deadlines and professional oversight.
• Use cloud accounting software to automate the collation of GST and PAYG figures, so your data is ready well before the deadline.

If keeping up with BAS obligations is taking time away from running your business, engaging bookkeeping services in Port Lincoln, like Eyre Accounting, is worth considering. Having your records maintained throughout the quarter means BAS preparation becomes a straightforward exercise rather than a last-minute rush.

Frequently Asked Questions

What happens if I lodge my BAS late, but I don’t actually owe any GST?

You can still receive a failure to lodge penalty even if your BAS shows a nil balance or a refund. According to the ATO’s penalty guidelines, the FTL penalty applies for failing to lodge the document by the due date — it is separate from any amount owing. This is a common misconception that catches some business owners off guard.

Can I get a BAS penalty waived if I missed the deadline?

Yes, in certain circumstances. The ATO has the discretion to remit all or part of an FTL penalty based on your individual situation. The ATO’s guidance on requesting remission of interest and failure to lodge penalties outlines the factors considered, including your lodgement history, the reason for the delay, and how quickly you took action.

Does using a bookkeeper or BAS agent give me more time to lodge?

Yes. Registered BAS agents operate under the ATO’s BAS agent lodgment program, which provides extended due dates for eligible quarterly activity statements — well beyond the standard deadlines. For business owners on the Eyre Peninsula looking to reduce compliance pressure, engaging bookkeeping services in Port Lincoln, such as those that are provided by Eyre Accounting, through a registered BAS agent can provide both extended time and professional accuracy.