The Business Activity Statement (BAS) is one of the most important obligations for any Australian business registered for GST. Yet it's also one of the most commonly misunderstood. Late lodgements, incorrect amounts, and missing items cost Australian businesses millions in penalties and interest every year.

This guide walks you through everything you need to know about lodging your BAS correctly and on time for FY2024–25.

What Is a BAS?

A Business Activity Statement is a form you submit to the ATO to report your business's tax obligations for a specific period. Depending on your registration and the size of your business, it may include:

Who Needs to Lodge a BAS?

You must lodge a BAS if your business is registered for GST. You must register for GST if your annual turnover is $75,000 or more ($150,000 for non-profit organisations). Taxi and ride-sharing drivers must register regardless of turnover.

✅ Under the $75,000 threshold?

If your turnover is under $75,000, you can choose to register for GST voluntarily. If you do, you must lodge a BAS. If you don't register, you don't charge GST and can't claim GST credits — but you also have no BAS obligation.

BAS Due Dates for 2024–25

Most small businesses lodge quarterly. The due dates for FY2024–25 are (or use our BAS Due Date Calculator):

Q1
July – September 2024
Due: 28 October 2024
Q2
October – December 2024
Due: 28 February 2025
Q3
January – March 2025
Due: 28 April 2025
Q4
April – June 2025
Due: 28 July 2025
💡 Using a registered BAS agent?

If you use a registered tax or BAS agent (like Digitwise Consulting), you generally get an extended lodgement deadline — typically an extra month. This is one of the key benefits of using a professional.

Monthly lodgers (generally businesses with turnover over $20 million) must lodge by the 21st of the following month. Annual lodgers (small businesses with turnover under $75,000 who have chosen to lodge annually) must lodge by 31 October.

What to Include in Your BAS

The exact labels on your BAS will depend on your registrations. The most common labels are:

The amount you pay (or get refunded) is the difference between 1A and 1B. If you charged more GST than you paid, you pay the difference. If you paid more GST than you charged (common in slow periods), you get a refund.

GST — What to Report

The standard GST rate in Australia is 10%. You must charge GST on most goods and services you sell and can claim back the GST on most goods and services you purchase for your business.

GST-free supplies (you don't charge GST, but can still claim input tax credits):

⚠️ Don't confuse GST-free with input-taxed supplies

Input-taxed supplies (like residential rent and most financial services) are different from GST-free. With input-taxed supplies, you neither charge GST nor claim GST credits on related purchases.

PAYG Withholding and Instalments

If you have employees, your BAS will also include a section for PAYG withholding — the tax you've withheld from your employees' wages and need to remit to the ATO.

If you earn business or investment income and the ATO has determined you should pay tax in advance, you may also be required to pay PAYG instalments — quarterly prepayments of your expected income tax for the year.

How to Lodge Your BAS

1
Reconcile your accounts

Before lodging, reconcile your bank statements against your accounting records. Every transaction should be coded correctly in Xero, MYOB or QuickBooks.

2
Run your GST report

In your accounting software, run the GST summary report for the quarter. This gives you your G1, G10, G11, 1A and 1B figures.

3
Check for missing transactions

Look for any supplier invoices or receipts not yet entered. Missing input tax credits mean you're overpaying GST.

4
Lodge via ATO Online, myGov, or your BAS agent

You can lodge directly through ATO Business Portal, or through your accounting software if it has lodgement integration. Your BAS agent can lodge on your behalf.

5
Pay the amount owing (or receive your refund)

Payment is due by the same date as lodgement. If you're owed a refund, the ATO typically processes it within 14 days.

Common BAS Mistakes to Avoid

Late Lodgement Penalties

The ATO takes late BAS lodgement seriously. Penalties are calculated in penalty units (currently $222 per unit) and scale with how late you are:

General interest charge (GIC) also applies to unpaid amounts from the due date until payment — currently running at approximately 11% per annum.

⚠️ Outstanding BAS returns

If you have outstanding BAS returns from prior periods, lodge them as soon as possible. The ATO is more likely to waive penalties for voluntary disclosure than for returns they chase up themselves.

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Disclaimer: This article is for general information only and does not constitute tax or BAS agent advice. Individual circumstances vary. Consult a registered BAS or tax agent for advice specific to your situation. ATO rules and due dates may change.