September 2025 Business Calendar: Key Dates and Tips for Australian Small Business Owners
- Leonie Martin
- Sep 1
- 3 min read
September marks the end of Quarter 1 in the 2025–26 financial year—a great time to pause, check in on your numbers, and make sure you’re staying on track with compliance.
Staying ahead of your obligations not only avoids ATO penalties but also gives you clarity and control over your cash flow.
Here are the key dates to mark in your calendar for September 2025:
Key Dates for September 2025:
📌 Stay organised and ahead of your deadlines.
📅 7 September 2025 📌 Father's Day
Take a moment to celebrate the dads in your life—and consider how your business can join in. From special offers to simple social media shout-outs, it’s a chance to connect with your audience in a genuine way.
📅 7 September 2025 📌 Payroll Tax – Monthly Lodgement (August wages)
If you’re registered for payroll tax in your state or territory, your return and payment for August 2025 wages are due.
📅 22 September 2025📌 Monthly BAS Due (August)
Business and Instalment Activity Statements for August must be lodged and paid by today. Getting this sorted on time saves you stress later—and ensures you stay in the ATO’s good books.
📅 30 September 2025📌 2025 FY STP Finalisation (Closely Held Payees for Larger Employers)
If you’re a larger employer with closely held payees (such as family members or directors), today is the final deadline to complete your Single Touch Payroll finalisation for the 2025 financial year.
Real-World Tips for Staying Ahead of September Deadlines
September is the end of the first quarter of the 2025–26 financial year. It’s the perfect time to tidy up your books, review cash flow, and make sure your compliance stays on track.
💸 Super tight? Get cash flow spring-ready.
Problem: You’ve covered wages, but now BAS and payroll tax hit in the same month and your bank account feels the squeeze.
Tip: Spring is the perfect time to review your cash flow. Break big obligations into smaller weekly transfers into a separate account. By the time deadlines roll around, the money’s already there.
🌿 Still drowning in paper? Go digital.
Problem: You’re wasting time chasing invoices, receipts, and reports across emails and filing cabinets.
Tip: A “spring clean” isn’t just for your office. Digitise your paperwork, connect your accounting software with apps like Hubdoc or Dext, and save hours each month. The more you automate, the easier every BAS feels.
📅 Too many moving parts? Simplify your calendar.
Problem: You’re relying on memory or scattered reminders — and it only takes one slip to cop a late fee.
Tip: Consolidate everything into one calendar. Colour-code compliance vs. operational tasks. Set reminders a week ahead so deadlines never sneak up.
🌸 New season, new habits.
Problem: You keep running your business the same way, even though small inefficiencies are costing you time, energy, and headspace.
Tip: Treat September like a reset button. Use the start of spring to review your systems — schedule super earlier, set up cash flow buffers, and streamline payroll reporting. Fresh habits now set you up for smoother growth over the rest of the year.
📈 Pricing stuck in winter?
Problem: Costs are creeping up — wages, rent, suppliers — but you haven’t reviewed your pricing since last year. Margins get thinner every month.
Tip: Use September’s fresh start to reassess your pricing. Even a small adjustment or introducing tiered options can protect your profit without scaring off clients. Spring is a natural time to refresh your offers.
Stay Ahead Without the Stress
When you’re busy running a business, compliance dates can creep up faster than you think. Missing one can mean unnecessary penalties and extra admin.
That’s where HelloLedger steps in. We keep your tax, payroll, BAS, and super obligations on track — so you have the peace of mind to focus on growth, clients, and the parts of business you actually enjoy.
Let’s chat today! 💬📞
