BAS Lodgement Guide: When, How, and What Australian Businesses Need to Report
If your business is registered for GST, lodging a Business Activity Statement (BAS) is not optional. With STP Phase 2 now mandatory, accurate payroll reporting supports your BAS process. Here's a practical guide to getting it right and avoiding ATO penalties.
What Is a BAS?
A Business Activity Statement is a form submitted to the Australian Taxation Office (ATO) that reports your GST, PAYG withholding, PAYG instalments, and other tax obligations.
When Is Your BAS Due?
| Lodgement Frequency | Due Date |
|---|---|
| Monthly | 21st day of the following month |
| Quarterly ( lodged by you) | 28 days after the end of the quarter |
| Quarterly (lodged by tax agent) | Usually 28 days after the standard due date |
Key quarterly dates for 2026:
- Q3 (Jan–Mar): 28 April 2026
- Q4 (Apr–Jun): 28 July 2026
How to Lodge
- Online via myGov — Linked to the ATO, this is the simplest method for most small businesses
- Through your accountant or tax agent — Recommended if your affairs are complex
- By phone — Available for businesses that report the same amount each period
- By mail — Paper BAS forms are still available but take longer to process
What to Report
Your BAS typically includes:
- GST — GST on sales (1A) and GST on purchases (1B)
- PAYG withholding — Tax withheld from employee wages
- PAYG instalments — Pre-paid income tax for the year
- FBT instalments — If applicable
Common Mistakes
- Missing the deadline — The ATO charges a failure-to-lodge penalty of $313 per 28-day period (up to $1,565 for individuals)
- Incorrect GST classification — Ensure you understand what is and isn't subject to GST
- Not reconciling before lodging — Cross-check your BAS figures against your accounting software
- Forgetting to claim credits — You're entitled to GST credits on business purchases
How Reguladar Helps
Reguladar tracks your BAS due dates, sends reminders before each deadline, and shows you exactly what needs to be lodged — alongside all your other small business compliance obligations. Never miss a BAS deadline again.
Try Reguladar free to see your upcoming tax obligations.
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