BAS activity statements in Australia are required for businesses registered for GST and must be lodged monthly or quarterly, depending on turnover.
If you run a small business in Australia, you’ve probably heard of a business activity statement (BAS), and it may feel a bit overwhelming at first.
For many small business owners, BAS statement time means paperwork, calculations, and stress about getting it right. But once you know how it all works, it is not so difficult.
This guide will tell you what BAS is, how it works, how to calculate it, and how to complete a BAS statement.
What Is BAS in Australia?
BAS stands for business activity statement. It is a document that you need to submit to the Australian Taxation Office (ATO) to pay certain taxes.
A BAS statement is the official document that the ATO sends to businesses that are registered for GST. You need to use this document to report:
- Goods and Services Tax (GST)
- PAYG withholding (if you have employees)
- PAYG instalments (in some cases)
In Australia, you need to submit a BAS if your business is registered for GST.
You need to register for GST if your turnover is:
- AUD 75,000 or more (most businesses)
- AUD 150,000 or more (non-profit organisations)
So if you’re running a growing business, chances are that business activity statement Australia compliance applies to you.
In practical terms, BAS in accounting refers to the report businesses lodge with the ATO to summarise key tax obligations. It shows:
- The GST you collected from customers
- The GST you paid on business purchases
- Any PAYG tax withheld from employee wages
So if you’re running a growing business, chances are that business activity statement Australia compliance applies to you.
In practical terms, BAS in accounting refers to the report businesses lodge with the ATO to summarise key tax obligations. It shows:
- The GST you collected from customers
- The GST you paid on business purchases
- Any PAYG tax withheld from employee wages
In simple terms, a BAS statement is a summary of what you owe the ATO — or what the ATO owes you.
How Does BAS Work?
Many entrepreneurs want to understand how BAS works in practice.
Here’s the simple version.
- You collect GST on your sales.
- You pay GST on your business expenses.
- You calculate the difference.
- You lodge your BAS with the ATO.
- You either pay the balance or receive a refund.
How often do you lodge BAS?
It depends on your business turnover.
- Most small businesses lodge their BAS every quarter.
- Some businesses, which are larger, lodge their BAS every month.
The ATO will let you know how often you need to lodge.
BAS Statement Example (Simple Breakdown)
| Section | Description | Example (AUD) |
|---|---|---|
| G1 | Total sales | 50,000 |
| 1A | GST on sales | 5,000 |
| G11 | Purchases | 20,000 |
| 1B | GST on purchases | 2,000 |
| W2 | PAYG withheld | 3,000 |
How it works:
- GST collected: 5,000
- GST paid: 2,000
- Net GST payable: 3,000
If you also withheld 3,000 in PAYG, your total amount due becomes 6,000.
This illustrates how your BAS statement combines everything into one report.
How to Calculate BAS
If you’re wondering how to calculate BAS accurately, this simple formula gives you a starting point.
Net GST = GST on Sales (1A) – GST on Purchases (1B)
Then add:
- PAYG withholding
- PAYG instalments (if applicable)
Before calculating BAS, make sure you:
- Reconcile your bank account
- Make sure all invoices are accounted for
- Make sure that GST has been entered correctly
- Review your payroll numbers
How Do I Fill Out a BAS Statement?
Many business owners ask how to complete a BAS statement properly. Completing a BAS statement isn’t just about filling in boxes; it starts with having your accounts prepared correctly.
Step-by-step guide to completing BAS statement:
- Finalise bookkeeping for the period
- Reconcile bank accounts
- Check the GST report
- Check payroll amounts
- Check that amounts match the accounting software
- Log in through the ATO website or accounting software
Before submitting, make sure you’re aware of the current BAS due dates and whether you qualify for an extension through a registered agent. Missing a deadline can result in penalties and interest charges. If you’re unsure about the submission steps, our BAS lodgement guide explains how to complete your BAS online or through an agent.
BAS Statements for Sole Traders: What You Need to Know
If you are a sole proprietor, the BAS statements can be intimidating at first. Some common pitfalls include:
- Forgetting to set aside GST funds
- Blending personal and business expenses
- Lodging late
- Not maintaining proper tax invoices
Simple tips for sole traders:
- Maintain a business bank account separate from your personal one
- Set aside GST funds in a savings account
- Update your bookkeeping system weekly
- Do not lodge late
Understanding the Difference Between IAS and BAS
While both IAS and BAS are forms lodged with the ATO, they serve different purposes and apply to different reporting obligations.
What is the difference between IAS and BAS?
| Feature | BAS | IAS |
|---|---|---|
| Includes GST | Yes | No |
| Includes PAYG instalment | Yes | Yes |
| Lodgement cycle | Monthly or quarterly | Often monthly |
Many business owners confuse IAS and BAS. An IAS (Instalment Activity Statement) is usually prepared for months when GST is not required, but PAYG instalments are.
Accounting BAS: Common Mistakes to Avoid
When you are dealing with BAS for a small business, small mistakes can attract fines. Common mistakes include:
- Claiming GST without a valid tax invoice
- Incorrect GST codes
- Leaving out some sales
- Not reconciling accounts
- Lodging late
What Is BAS Tax?
You may have heard the term ‘BAS tax’. BAS tax is not a tax in itself. It is only a reference to the taxes that you are required to report in your BAS, which include:
- GST
- PAYG withholding
- PAYG instalments
BAS Due Dates in Australia
For most small businesses:
- Quarterly BAS is due on the 28th of the month after the quarter ends.
- Monthly BAS is usually due on the 21st of the following month.
However, due dates may vary in certain circumstances. Always check the latest due dates on the ATO website, as they can change.
Late lodgement may attract:
- Failure to lodge penalties
- General Interest Charges
It is important to keep track of your BAS due dates. You can review key deadlines in our guide to BAS due dates.
Final Thoughts
Many small business owners find BAS confusing, but it doesn’t have to be.
If you know what BAS is, how it works, and how to calculate it correctly, it becomes routine. The key is to keep your bookkeeping system up to date and check your figures before lodging.
If BAS is still confusing and stressful, seeking professional advice can save you time, reduce risk, and give you peace of mind. At Befree, we help small business owners stay on top of their BAS with accurate reporting, clear advice, and stress-free lodgement support.
Need help with your BAS? Talk to our team and get clear, reliable support that keeps your business compliant and stress-free.
Frequently Asked Questions About BAS Activity Statement
What date is BAS due in Australia?
BAS is due on the 28th of the month after your reporting period ends, and you might get an extension if you lodge your BAS or tax return through a registered BAS or tax agent.
Is BAS GST in Australia?
Is GST still 10% in Australia?
Is BAS the same as income tax?
What documents do I need for BAS?
You will need sales invoices, purchase invoices, bank statements, payroll records (if required), and your accounting reports showing GST liability and GST paid.