What is a Business Activity Statement (BAS)?
Purpose and Importance of BAS
A Business Activity Statement, also called BAS, is a form that businesses in Australia use to report important tax information to the Australian Taxation Office (ATO). BAS helps track how much Goods and Services Tax (GST), Pay As You Go (PAYG) tax, and other taxes your business needs to pay. It is essential for keeping your business legal and up to date with tax rules.
Who Needs to Lodge a BAS?
If you run a business and have registered for GST or PAYG, you must complete and lodge a BAS. This includes most companies, partnerships, sole traders and not-for-profit organizations registered with the ATO.
BAS Frequency in 2026
Most businesses send in their BAS every quarter. Some small businesses with lower GST can lodge annually. Big companies might need to lodge monthly. Check your ATO registration to see when you must lodge BAS.
Preparing for Your BAS: What You Need Before You Start
Essential Documents and Details Required
To prepare a Business Activity Statement, gather these items:
- Invoices and receipts for sales and purchases
- Bank statements
- Payroll data if you have employees
- Your Australian Business Number (ABN)
Choosing the Right Software or Portal (Updates for 2026)
In 2026, you can use ATO’s online portal or accounting software like MYOB, Xero, or QuickBooks, which connect directly to the ATO for BAS lodgment. Check if your business software supports BAS and is updated for 2026 requirements.
Keeping Accurate Records
Record all sales, purchases, and expenses clearly. Regularly update your records to avoid mistakes in your BAS. Good record keeping makes the BAS process quicker and more accurate.
Step-by-Step: How to Do Your Business Activity Statement
Step 1 – Gather Your BAS Reporting Details
Collect all documents and records mentioned earlier. Make sure sales and purchases are fully recorded for the BAS period you are reporting.
Step 2 – Completing the BAS Form (with Annotated Example)
- Start with your personal and business details: Name, ABN, BAS period.
- Enter total sales (G1 box on most forms).
- Calculate total GST received on sales and GST paid on purchases. Add these to the correct boxes.
- If you have employees, fill in PAYG Withholding amounts.
- Double check figures before moving onward.
Step 3 – Using Digital Lodgment Tools (ATO Online, Software Integration)
- Log into the ATO Business Portal with your myGovID.
- Choose the option to lodge a BAS.
- If using accounting software, select the BAS function. These tools can autofill many items for you.
- Review everything and confirm submission.
Step 4 – Submitting and Saving Your BAS
- Submit your BAS online through the ATO Portal or directly from your accounting software.
- Download and save a copy of the submitted BAS for your records.
- Keep copies for at least five years in case the ATO asks for them later.
Practical Example: Filling Out a BAS Form in 2026
Scenario Overview: Sample Small Business
Let’s imagine “EasyTech Supplies”, a business in technology sales. They report BAS quarterly and are registered for GST and PAYG.
Walkthrough of a Completed BAS Form
| Section | Example Entry |
|---|---|
| ABN | 12 345 678 910 |
| BAS Period | 1 April 2026 – 30 June 2026 |
| G1: Total Sales | $10,000 |
| 1A: GST Collected | $900 |
| 1B: GST Paid | $350 |
| W1: Total salaries, wages and other payments | $2,000 |
| W2: Amount withheld from payments | $300 |
Downloadable BAS Checklist (PDF/Excel Format)
BAS Checklist includes:
- Bank Statements
- Sales Invoices
- Purchase Receipts
- GST calculations
- Payroll Records
- Login details for ATO portal or software
You can find templates on the ATO website or create your own in Excel or PDF for each period.
Common Mistakes When Doing a Business Activity Statement—And How to Avoid Them
Data Entry Errors and GST Calculation Issues
Always check for typos. Make sure your GST is calculated correctly on sales and purchases. Use tools inside BAS software to double-check.
Timing Mistakes and Missed Deadlines
Put BAS due dates on your calendar. Lodging late can mean penalties from the ATO.
Forgotten Deductions and PAYG Withholding
Don’t miss out on claiming GST credits on business purchases. Also, remember to include all PAYG amounts if you pay employees.
Tips for First-Time BAS Lodgers
Where to Get Help (ATO and Accountant Support)
The ATO website has BAS guides, videos, and live chat. Accountants can also provide step-by-step help for your first BAS.
BAS Lodgment Extensions and Penalty Avoidance
If you can’t lodge on time, apply for an extension through the ATO portal before the deadline to avoid late penalties.
Best Practices for Staying Compliant in 2026
- Keep records up to date every month
- Use trusted accounting software
- Check ATO updates for any new rules
- Set reminders for BAS lodgment
FAQ: Business Activity Statement Questions
- What is included in a BAS? GST, PAYG, and other business taxes.
- How do I know my BAS reporting period? Check your ATO online account or registration letter.
- Can I lodge BAS myself or need an accountant? You can do it yourself or ask a registered tax agent.
Mini Glossary: Key BAS Terms Explained
- BAS: Business Activity Statement, a summary form for business taxes.
- ATO: Australian Taxation Office, the tax department of Australia.
- GST: Goods and Services Tax, a 10% tax on most goods and services.
- PAYG: Pay As You Go, a system for businesses to withhold tax from wages and some suppliers.
- ABN: Australian Business Number, your business’s unique ID.