Knowing your BAS due dates is important because late preparation can create unnecessary stress, rushed bookkeeping and payment surprises. Australian businesses can report GST monthly, quarterly or, in some cases, annually depending on turnover, registration status and ATO arrangements. This guide explains the standard monthly and quarterly BAS cycles, how due dates work, what can affect them and how to build a reliable BAS calendar.
What Is a BAS Reporting Cycle?
Your BAS reporting cycle determines how often you report relevant obligations to the Australian Taxation Office. For GST, the most common cycles are monthly and quarterly.
Quarterly BAS
Current ATO guidance generally allows quarterly GST reporting when GST turnover is below $20 million and the ATO has not required monthly reporting.
Monthly BAS
Businesses with GST turnover of $20 million or more generally report monthly, and some businesses may choose monthly reporting voluntarily.
Annual GST Reporting
Some voluntarily registered businesses with lower turnover may be eligible for annual reporting, subject to ATO rules.
What Are the Standard Quarterly BAS Due Dates?
The standard quarterly due dates currently published by the ATO are:
- Quarter 1: July to September — 28 October
- Quarter 2: October to December — 28 February
- Quarter 3: January to March — 28 April
- Quarter 4: April to June — 28 July
Can Quarterly BAS Due Dates Be Extended?
Some businesses may be eligible for additional time when lodging electronically or through a registered agent. The exact extension depends on the circumstances and current ATO lodgment programs, so businesses should confirm the due date shown in their ATO account or through their registered agent.
What Is the Monthly BAS Due Date?
For monthly reporting, the standard BAS due date is generally the 21st day of the month following the end of the taxable period. For example, a July monthly BAS is generally due on 21 August.
Why Monthly BAS Requires Stronger Bookkeeping Discipline
Monthly reporting gives businesses less time to correct missing transactions, reconcile accounts and review GST coding. A consistent month-end process becomes much more important.
How Do I Know Whether I Report Monthly or Quarterly?
Your reporting cycle can be checked through your ATO business account, activity statement notices or accounting records. Do not assume your cycle based only on business size.
Quarterly Reporting Is Common When
- GST turnover is below the monthly reporting threshold.
- The ATO has not required monthly reporting.
- The business has a standard quarterly reporting arrangement.
Monthly Reporting May Apply When
- GST turnover is $20 million or more.
- The business chooses monthly reporting.
- The ATO requires monthly reporting.
What Happens If a BAS Due Date Falls on a Weekend?
Payment and lodgment timing can be affected by weekends, public holidays and ATO administrative arrangements. Always confirm the due date shown for your specific activity statement rather than relying only on a generic calendar.
What Should You Do 30 Days Before BAS Is Due?
A good BAS process starts before the deadline. Waiting until the final week can make missing invoices and unreconciled accounts harder to resolve.
30-Day BAS Preparation Checklist
- Make sure bank feeds are current.
- Reconcile all business bank accounts.
- Review credit-card accounts.
- Follow up missing receipts.
- Check supplier invoices.
- Review sales records.
- Check GST coding.
- Review payroll balances where relevant.
What Should You Do 7 Days Before BAS Is Due?
- Complete final reconciliations.
- Review unusual GST transactions.
- Check large purchases and sales.
- Confirm payroll-related amounts.
- Review the draft BAS.
- Confirm the amount payable or refundable.
- Plan payment before the due date.
Why BAS Deadlines Become Stressful
BAS deadlines are usually difficult when the underlying bookkeeping is not current. The reporting itself is often the final step of a much larger record-keeping process.
Common Causes of BAS Delays
- Bank accounts have not been reconciled.
- Receipts are missing.
- GST coding is inconsistent.
- Supplier bills are incomplete.
- Payroll records do not match accounting records.
- Prior BAS adjustments are unresolved.
Can You Lodge BAS Early?
Businesses can often prepare and lodge once the reporting period has ended and the required information is complete. Early preparation can give the owner more time to plan for a payment.
Benefits of Early BAS Preparation
- More time to resolve errors.
- Better cash-flow planning.
- Less deadline pressure.
- Earlier visibility of GST payable.
What If You Miss a BAS Due Date?
If BAS is overdue, do not ignore it. Bring the records up to date, identify which periods are outstanding and check the current ATO requirements. Depending on circumstances, late lodgment or payment consequences can apply.
See our overdue BAS guide.
What Is the Difference Between BAS Lodgment and BAS Payment?
Lodgment is the submission of the activity statement. Payment is the transfer of any amount owed. Businesses should plan for both because lodging on time does not automatically mean payment has been made.
Why Cash-Flow Planning Matters
A business can be profitable but still struggle to pay BAS if GST collected has been used for other operating expenses. Regular cash-flow monitoring helps reduce this risk.
How Can Xero Help Manage BAS Deadlines?
Xero can help organise GST transactions, bank reconciliations and BAS reporting when configured correctly. The software does not replace review, but it can make month-end processes more consistent.
See our Xero BAS guide.
How Can QuickBooks or MYOB Help?
Other accounting platforms also support GST tracking and activity statement workflows. The important factor is that the tax settings, chart of accounts and transaction coding are correct.
How to Build a BAS Calendar for Your Business
A BAS calendar should include more than the final due date. Add internal bookkeeping deadlines so the work is completed gradually.
Example Quarterly BAS Workflow
- Monthly: reconcile accounts and review GST coding.
- First week after quarter end: complete final reconciliations.
- Second week: review missing documents and adjustments.
- Third week: review draft BAS.
- Before due date: lodge and arrange payment.
Example Monthly BAS Workflow
- Weekly: keep bank feeds and invoices current.
- Month end: reconcile accounts.
- First week of next month: review GST coding.
- Second week: prepare BAS and resolve issues.
- Before the 21st: lodge and arrange payment.
Can a BAS Agent Get Different Due Dates?
Registered agents may have access to different lodgment programs for eligible clients. Do not assume an extension applies automatically. Confirm the actual due date for your business.
Common BAS Date Mistakes
Using the Same Date Every Quarter Without Checking
Generic calendars are useful, but your actual due date may differ because of agent arrangements or administrative changes.
Waiting Until the Due Date to Start Bookkeeping
This leaves little time to fix errors or collect missing records.
Confusing GST Reporting Frequency With Payroll Frequency
Your GST cycle and payroll cycle are separate processes. A business may run payroll weekly but report GST quarterly.
Forgetting the Payment Date
BAS preparation should include cash-flow planning so the business is ready for any payment.
Quick answer
Quarterly BAS is generally due on 28 October, 28 February, 28 April and 28 July. Monthly BAS is generally due on the 21st of the following month. Always confirm the date for your specific statement.
Frequently Asked Questions
Is BAS always due on the 28th?
No. The standard quarterly dates use the 28th, while monthly BAS is generally due on the 21st of the following month.
Can I change from quarterly to monthly BAS?
In some circumstances businesses can choose a different reporting cycle. Check current ATO eligibility and process requirements.
What if I cannot pay BAS on time?
Do not avoid lodgment. Review ATO options and seek appropriate professional support for your circumstances.
Does my bookkeeper need the records before the due date?
Yes. Providing information early gives enough time for reconciliation and review.
Can I prepare BAS from unreconciled books?
You should avoid relying on unreconciled records because missing or duplicated transactions can affect the figures.
Related Guides
- BAS Lodgement Services Melbourne Guide
- GST Registration Guide
- BAS Preparation Checklist
- Bookkeeping Services Melbourne Guide
- ATO BAS Due Date Guidance
How to Avoid BAS Deadline Problems Throughout the Year
The easiest way to manage BAS deadlines is to treat BAS preparation as a regular bookkeeping process rather than a quarterly emergency. Keep bank feeds current, reconcile monthly and review GST coding as transactions are entered. This spreads the work across the reporting period.
Monthly BAS Readiness Routine
- Reconcile all bank accounts.
- Review uncoded transactions.
- Check large purchases.
- Review customer invoices.
- Review supplier bills.
- Check payroll clearing accounts.
- Investigate unusual GST codes.
If the books are BAS-ready every month, the end-of-quarter process becomes mainly a final review instead of a large cleanup project.
Should You Use Calendar Reminders for BAS?
Yes. Add both the statutory due date and earlier internal deadlines. For example, set a bookkeeping deadline two weeks before the BAS due date and a review deadline one week before. This gives the business time to find missing invoices and plan for payment.
Owners should also confirm the actual date shown in ATO systems because generic calendar dates may not reflect agent arrangements or specific circumstances.
Keeping a simple BAS calendar beside your monthly bookkeeping checklist can also help staff understand which records need to be finalised first.
This keeps the process consistent.
Get BAS Deadline Support
TNS Accounting helps Melbourne businesses keep bookkeeping current and prepare BAS-ready records. Contact TNS Accounting to discuss your BAS cycle and bookkeeping process.
